| Tuesday, January 11 |
| Future Pirate Jermaine Allensworth is born in Anderson, IN. |
| Wednesday, January 12 |
| Future Pirate Rich Loiselle is born in Neenah, WI. |
| Sunday, January 23 |
| Former Pirate Fred Nicholson dies in Kilgore, TX at the age of 78. |
| Friday, January 28 |
| Future Pirate Chris Peters is born in Fort Thomas, KY. |
| Saturday, March 4 |
| Future Pirate Bruce Aven is born in Orange, TX. |
| Thursday, March 16 |
| Former Pirate Pie Traynor dies in Pittsburgh, PA at the age of 73. |
| Saturday, April 15 |
| » Lost to Mets (1-0), 4-0 | Shea Stadium (0-1) | 0-1 | |
| » Starters: Dock Ellis vs Tom Seaver | Second | 1 out |
| Sunday, April 16 |
| » Defeated Mets (1-1), 2-0 | Shea Stadium (1-1) | 1-1 | |
| » Starters: Steve Blass vs Gary Gentry | Second | 1 out |
| Tuesday, April 18 |
| » Lost to Cubs (2-1), 6-4 | Three Rivers Stadium (0-1) | 1-2 | |
| » Starters: Milt Pappas vs Bob Moose | Fourth | 2 out |
| Wednesday, April 19 |
| » Defeated Cubs (2-2), 5-2 | Three Rivers Stadium (1-1) | 2-2 | |
| » Starters: Juan Pizarro vs Bob Johnson | Third | 1½ out |
| Thursday, April 20 |
| » Defeated Cubs (2-3), 7-5 | Three Rivers Stadium (2-1) | 3-2 | Won 2 |
| » Starters: Fergie Jenkins vs Dock Ellis | Second | 1 out |
| Friday, April 21 |
| » Defeated Phillies (3-3), 3-2 | Veteran's Stadium (1-0) | 4-2 | Won 3 |
| » Starters: Steve Blass vs Dick Selma | Second | 1 out |
| Sunday, April 23 |
| » Lost to Phillies (4-3), 5-4 | Veteran's Stadium (1-1) | 4-3 | |
| » Starters: Bob Moose vs Woodie Fryman | Third | 1½ out |
| Tuesday, April 25 |
| » Defeated Reds (2-6), 5-2 | Three Rivers Stadium (3-1) | 5-3 | |
| » Starters: Jim Merritt vs Bob Johnson | Second | ½ out |
| Wednesday, April 26 |
| » Lost to Reds (3-6), 7-6 | Three Rivers Stadium (3-2) | 5-4 | |
| » Starters: Gary Nolan vs Steve Blass | Third | 1½ out |
| Future Pirate Francisco Cordova is born in Veracruz, Mexico. |
| Thursday, April 27 |
| » Lost to Reds (4-6), 5-4 | Three Rivers Stadium (3-3) | 5-5 | Lost 2 |
| » Starters: Don Gullett vs Nelson Briles | Fourth | 2½ out |
| Friday, April 28 |
| » Lost to Braves (5-8), 13-5 | Three Rivers Stadium (3-4) | 5-6 | Lost 3 |
| » Starters: Pat Jarvis vs Bob Moose | Fourth | 3½ out |
| Saturday, April 29 |
| » Lost to Braves (6-8), 9-5 | Three Rivers Stadium (3-5) | 5-7 | Lost 4 |
| » Starters: Tom Kelley vs Luke Walker | Third | 3½ out |
| Sunday, April 30 |
| » Lost to Braves (7-8), 6-1 | Three Rivers Stadium (3-6) | 5-8 | Lost 5 |
| » Starters: Phil Niekro vs Bob Johnson | Fourth | 4 out |
| Monday, May 1 |
| » Lost to Astros (11-4), 9-8 | Three Rivers Stadium (3-7) | 5-9 | Lost 6 |
| » Starters: Dave Roberts vs Steve Blass | Fourth | 4½ out |
| Wednesday, May 3 |
| » Defeated Astros (11-5), 3-2 | Three Rivers Stadium (4-7) | 6-9 | |
| » Starters: Jerry Reuss vs Dock Ellis | Fourth | 5 out |
| Friday, May 5 |
| » Lost to Reds (8-9), 5-4 | Riverfront Stadium (0-1) | 6-10 | |
| » Starters: Bob Johnson vs Gary Nolan | Fifth | 5 out |
| Saturday, May 6 |
| » Defeated Reds (8-10), 8-1 | Riverfront Stadium (1-1) | 7-10 | |
| » Starters: Steve Blass vs Pedro Borbon | Fifth | 4 out |
| Sunday, May 7 |
| » Defeated Reds (8-11), 9-6 | Riverfront Stadium (2-1) | 8-10 | Won 2 |
| » Starters: Nelson Briles vs Jack Billingham | Fourth | 4 out |
| Tuesday, May 9 |
| » Defeated Braves (8-14), 5-2 | Atlanta-Fulton County Stadium (1-0) | 9-10 | Won 3 |
| » Starters: Dock Ellis vs Tom Kelley | Fourth | 3½ out |
| Wednesday, May 10 |
| » Lost to Braves (9-14), 8-4 | Atlanta-Fulton County Stadium (1-1) | 9-11 | |
| » Starters: Bob Johnson vs Phil Niekro | Fifth | 4½ out |
| Friday, May 12 |
| » Defeated Astros (13-9), 4-2 | Astrodome (1-0) | 10-11 | |
| » Starters: Steve Blass vs Larry Dierker | Fifth | 4½ out |
| Saturday, May 13 |
| » Defeated Astros (13-10), 6-1 | Astrodome (2-0) | 11-11 | Won 2 |
| » Starters: Bob Moose vs Ken Forsch | Fourth | 4½ out |
| Sunday, May 14 |
| » Lost to Astros (14-10), 7-6 | Astrodome (2-1) | 11-12 | |
| » Starters: Nelson Briles vs Don Wilson | Fourth | 5½ out |
| Monday, May 15 |
| » Defeated Cardinals (10-17), 4-1 | Three Rivers Stadium (5-7) | 12-12 | |
| » Starters: Bob Gibson vs Dock Ellis | Fourth | 5½ out |
| Tuesday, May 16 |
| » Defeated Cardinals (10-18), 4-3 | Three Rivers Stadium (6-7) | 13-12 | Won 2 |
| » Starters: Rick Wise vs Luke Walker | Third | 5½ out |
| Wednesday, May 17 |
| » Defeated Cardinals (10-19), 12-0 | Three Rivers Stadium (7-7) | 14-12 | Won 3 |
| » Starters: Reggie Cleveland vs Steve Blass | Third | 5½ out |
| Friday, May 19 |
| » Defeated Expos (13-16), 8-0 | Three Rivers Stadium (8-7) | 15-12 | Won 4 |
| » Starters: Bill Stoneman vs Bob Moose | Second | 6 out |
| Saturday, May 20 |
| » Defeated Expos (13-17), 6-0 | Three Rivers Stadium (9-7) | 16-12 | Won 5 |
| » Starters: Carl Morton vs Dock Ellis | Second | 6½ out |
| Sunday, May 21 |
| » Defeated Expos (13-18), 1-0 | Three Rivers Stadium (10-7) | 17-12 | Won 6 |
| » Starters: Ernie McAnally vs Luke Walker | Second | 6 out |
| » Defeated Expos (13-19), 5-3 | Three Rivers Stadium (11-7) | 18-12 | Won 7 |
| » Starters: Steve Renko vs Bob Johnson | Second | 6 out |
| Tuesday, May 23 |
| » Defeated Cardinals (12-22), 6-2 | Busch Stadium II (1-0) | 19-12 | Won 8 |
| » Starters: Steve Blass vs Reggie Cleveland | Second | 5 out |
| Wednesday, May 24 |
| » Defeated Cardinals (12-23), 9-4 | Busch Stadium II (2-0) | 20-12 | Won 9 |
| » Starters: Bob Moose vs Scipio Spinks | Second | 4 out |
| Thursday, May 25 |
| » Lost to Cardinals (13-23), 4-2 | Busch Stadium II (2-1) | 20-13 | |
| » Starters: Dock Ellis vs Bob Gibson | Second | 5 out |
| Friday, May 26 |
| » Defeated Phillies (15-20), 6-4 | Three Rivers Stadium (12-7) | 21-13 | |
| » Starters: Steve Carlton vs Nelson Briles | Second | 4 out |
| Saturday, May 27 |
| » Lost to Phillies (16-20), 2-1 | Three Rivers Stadium (12-8) | 21-14 | |
| » Starters: Bill Champion vs Bob Johnson | Second | 5 out |
| Sunday, May 28 |
| » Defeated Phillies (16-21), 6-5 | Three Rivers Stadium (13-8) | 22-14 | |
| » Starters: Dick Selma vs Steve Blass | Second | 4 out |
| Former Pirate Al Gerheauser dies in Springfield, MO at the age of 55. |
| Monday, May 29 |
| » Defeated Phillies (16-22), 7-3 | Three Rivers Stadium (14-8) | 23-14 | Won 2 |
| » Starters: Woodie Fryman vs Luke Walker | Second | 3½ out |
| » Defeated Phillies (16-23), 4-2 | Three Rivers Stadium (15-8) | 24-14 | Won 3 |
| » Starters: Ken Reynolds vs Bob Moose | Second | 3½ out |
| Wednesday, May 31 |
| » Lost to Expos (18-22), 3-2 | Parc Jarry (0-1) | 24-15 | |
| » Starters: Nelson Briles vs Ernie McAnally | Second | 4½ out |
| Friday, June 2 |
| » Lost to Giants (17-31), 7-4 | Candlestick Park (0-1) | 24-16 | Lost 2 |
| » Starters: Bob Johnson vs Juan Marichal | Second | 5 out |
| Future Pirate Chance Sanford is born in Houston, TX. |
| Saturday, June 3 |
| » Defeated Giants (17-32), 4-3 | Candlestick Park (1-1) | 25-16 | |
| » Starters: Steve Blass vs Sam McDowell | Second | 5 out |
| Sunday, June 4 |
| » Defeated Giants (17-33), 4-3 | Candlestick Park (2-1) | 26-16 | Won 2 |
| » Starters: Luke Walker vs Ron Bryant | Second | 3½ out |
| » Defeated Giants (17-34), 9-1 | Candlestick Park (3-1) | 27-16 | Won 3 |
| » Starters: Bruce Kison vs Charlie Williams | Second | 3½ out |
| Wednesday, June 7 |
| » Defeated Padres (16-30), 12-5 | San Diego/Jack Murphy Stadium (1-0) | 28-16 | Won 4 |
| » Starters: Nelson Briles vs Fred Norman | Second | 2½ out |
| » Defeated Padres (16-31), 1-0 | San Diego/Jack Murphy Stadium (2-0) | 29-16 | Won 5 |
| » Starters: Dock Ellis vs Clay Kirby | Second | 2½ out |
| » Major-league debuts: Dave Roberts (Padres) |
| Thursday, June 8 |
| » Defeated Padres (16-32), 11-2 | San Diego/Jack Murphy Stadium (3-0) | 30-16 | Won 6 |
| » Starters: Bob Moose vs Steve Arlin | Second | 1½ out |
| Friday, June 9 |
| » Defeated Dodgers (30-20), 5-1 | Dodger Stadium (1-0) | 31-16 | Won 7 |
| » Starters: Steve Blass vs Don Sutton | Second | ½ out |
| Saturday, June 10 |
| » Lost to Dodgers (31-20), 2-1 | Dodger Stadium (1-1) | 31-17 | |
| » Starters: Luke Walker vs Claude Osteen | Second | 1½ out |
| Sunday, June 11 |
| » Defeated Dodgers (31-21), 7-5 | Dodger Stadium (2-1) | 32-17 | |
| » Starters: Bruce Kison vs Al Downing | Second | ½ out |
| Tuesday, June 13 |
| Future Pirate Darrell May is born in San Bernardino, CA. |
| Wednesday, June 14 |
| » Lost to Giants (19-39), 3-1 | Three Rivers Stadium (15-9) | 32-18 | |
| » Starters: Sam McDowell vs Dock Ellis | Second | 1½ out |
| Thursday, June 15 |
| » Defeated Giants (19-40), 4-1 | Three Rivers Stadium (16-9) | 33-18 | |
| » Starters: Steve Stone vs Nelson Briles | First | -- |
| » Defeated Giants (19-41), 9-7 | Three Rivers Stadium (17-9) | 34-18 | Won 2 |
| » Starters: Ron Bryant vs Bob Moose | First | -- |
| Friday, June 16 |
| » Defeated Padres (18-37), 2-1 | Three Rivers Stadium (18-9) | 35-18 | Won 3 |
| » Starters: Fred Norman vs Steve Blass | First | -- |
| Saturday, June 17 |
| » Lost to Padres (19-37), 4-0 | Three Rivers Stadium (18-10) | 35-19 | |
| » Starters: Clay Kirby vs Luke Walker | First | -- |
| Sunday, June 18 |
| » Lost to Padres (20-37), 1-0 | Three Rivers Stadium (18-11) | 35-20 | Lost 2 |
| » Starters: Steve Arlin vs Bruce Kison | Second | ½ out |
| Monday, June 19 |
| » Defeated Dodgers (32-26), 13-3 | Three Rivers Stadium (19-11) | 36-20 | |
| » Starters: Don Sutton vs Dock Ellis | First | -- |
| Wednesday, June 21 |
| » Lost to Dodgers (33-26), 5-3 | Three Rivers Stadium (19-12) | 36-21 | |
| » Starters: Claude Osteen vs Bob Moose | First | -- |
| Friday, June 23 |
| » Defeated Cubs (34-24), 4-2 | Wrigley Field (1-0) | 37-21 | |
| » Starters: Steve Blass vs Fergie Jenkins | First | -- |
| Saturday, June 24 |
| » Defeated Cubs (34-25), 3-1 | Wrigley Field (2-0) | 38-21 | Won 2 |
| » Starters: Nelson Briles vs Bill Hands | First | -- |
| Sunday, June 25 |
| » Defeated Cubs (34-26), 9-2 | Wrigley Field (3-0) | 39-21 | Won 3 |
| » Starters: Dock Ellis vs Burt Hooton | First | -- |
| Monday, June 26 |
| » Lost to Mets (38-25), 4-2 | Shea Stadium (1-2) | 39-22 | |
| » Starters: Bob Moose vs Jerry Koosman | First | -- |
| Tuesday, June 27 |
| » Lost to Mets (39-25), 7-4 | Shea Stadium (1-3) | 39-23 | Lost 2 |
| » Starters: Bruce Kison vs Jim McAndrew | First | -- |
| Wednesday, June 28 |
| » Lost to Expos (29-36), 3-1 | Three Rivers Stadium (19-13) | 39-24 | Lost 3 |
| » Starters: Bill Stoneman vs Steve Blass | First | -- |
| Thursday, June 29 |
| » Defeated Expos (29-37), 9-0 | Three Rivers Stadium (20-13) | 40-24 | |
| » Starters: Ernie McAnally vs Nelson Briles | First | -- |
| Friday, June 30 |
| » Lost to Cubs (37-29), 4-3 | Three Rivers Stadium (20-14) | 40-25 | |
| » Starters: Rick Reuschel vs Dock Ellis | First | -- |
| Saturday, July 1 |
| » Defeated Cubs (37-30), 4-3 | Three Rivers Stadium (21-14) | 41-25 | |
| » Starters: Fergie Jenkins vs Bob Moose | First | -- |
| Sunday, July 2 |
| » Defeated Cubs (37-31), 7-4 | Three Rivers Stadium (22-14) | 42-25 | Won 2 |
| » Starters: Bill Hands vs Bruce Kison | First | -- |
| Monday, July 3 |
| » Defeated Cubs (37-32), 3-2 | Three Rivers Stadium (23-14) | 43-25 | Won 3 |
| » Starters: Burt Hooton vs Steve Blass | First | -- |
| Tuesday, July 4 |
| » Lost to Astros (44-29), 6-0 | Astrodome (2-2) | 43-26 | |
| » Starters: Nelson Briles vs Larry Dierker | First | -- |
| Wednesday, July 5 |
| » Defeated Astros (44-30), 6-4 | Astrodome (3-2) | 44-26 | |
| » Starters: Dock Ellis vs Ken Forsch | First | -- |
| Thursday, July 6 |
| » Defeated Astros (44-31), 7-3 | Astrodome (4-2) | 45-26 | Won 2 |
| » Starters: Bob Moose vs Don Wilson | First | -- |
| Friday, July 7 |
| » Defeated Braves (35-40), 10-2 | Atlanta-Fulton County Stadium (2-1) | 46-26 | Won 3 |
| » Starters: Luke Walker vs Tom Kelley | First | -- |
| » Lost to Braves (36-40), 3-2 | Atlanta-Fulton County Stadium (2-2) | 46-27 | |
| » Starters: Bruce Kison vs Jim Hardin | First | -- |
| Saturday, July 8 |
| » Defeated Braves (36-41), 5-3 | Atlanta-Fulton County Stadium (3-2) | 47-27 | |
| » Starters: Steve Blass vs Ron Reed | First | -- |
| Sunday, July 9 |
| » Defeated Braves (36-42), 7-4 | Atlanta-Fulton County Stadium (4-2) | 48-27 | Won 2 |
| » Starters: Nelson Briles vs Denny McLain | First | -- |
| Tuesday, July 11 |
| » Lost to Reds (46-31), 5-0 | Riverfront Stadium (2-2) | 48-28 | |
| » Starters: Bob Moose vs Jack Billingham | First | -- |
| Wednesday, July 12 |
| » Lost to Reds (47-31), 6-3 | Riverfront Stadium (2-3) | 48-29 | Lost 2 |
| » Starters: Luke Walker vs Wayne Simpson | First | -- |
| Thursday, July 13 |
| » Lost to Reds (48-31), 2-0 | Riverfront Stadium (2-4) | 48-30 | Lost 3 |
| » Starters: Steve Blass vs Gary Nolan | First | -- |
| Future Pirate Clint Sodowsky is born in Ponca City, OK. |
| Friday, July 14 |
| » Defeated Astros (48-35), 5-2 | Three Rivers Stadium (24-14) | 49-30 | |
| » Starters: Larry Dierker vs Nelson Briles | First | -- |
| Saturday, July 15 |
| » Defeated Astros (48-36), 5-1 | Three Rivers Stadium (25-14) | 50-30 | Won 2 |
| » Starters: Ken Forsch vs Dock Ellis | First | -- |
| Sunday, July 16 |
| » Defeated Astros (48-37), 3-2 | Three Rivers Stadium (26-14) | 51-30 | Won 3 |
| » Starters: Tom Griffin vs Bob Moose | First | -- |
| » Defeated Astros (48-38), 3-2 | Three Rivers Stadium (27-14) | 52-30 | Won 4 |
| » Starters: Don Wilson vs Bruce Kison | First | -- |
| Monday, July 17 |
| » Defeated Braves (38-47), 6-5 | Three Rivers Stadium (28-14) | 53-30 | Won 5 |
| » Starters: Ron Schueler vs Luke Walker | First | -- |
| Tuesday, July 18 |
| » Lost to Braves (39-47), 4-2 | Three Rivers Stadium (28-15) | 53-31 | |
| » Starters: Ron Reed vs Steve Blass | First | -- |
| Wednesday, July 19 |
| » Defeated Braves (39-48), 8-3 | Three Rivers Stadium (29-15) | 54-31 | |
| » Starters: Phil Niekro vs Nelson Briles | First | -- |
| » Major-league debuts: Larvell Blanks (Braves) |
| Friday, July 21 |
| » Lost to Reds (54-32), 11-5 | Three Rivers Stadium (29-16) | 54-32 | |
| » Starters: Jack Billingham vs Dock Ellis | First | -- |
| Saturday, July 22 |
| » Lost to Reds (55-32), 6-3 | Three Rivers Stadium (29-17) | 54-33 | Lost 2 |
| » Starters: Wayne Simpson vs Bob Moose | First | -- |
| Sunday, July 23 |
| » Defeated Reds (55-33), 3-2 | Three Rivers Stadium (30-17) | 55-33 | |
| » Starters: Ross Grimsley vs Steve Blass | First | -- |
| Thursday, July 27 |
| » Lost to Mets (50-38), 1-0 | Three Rivers Stadium (30-18) | 55-34 | |
| » Starters: Jon Matlack vs Nelson Briles | First | -- |
| » Defeated Mets (50-39), 7-5 | Three Rivers Stadium (31-18) | 56-34 | |
| » Starters: Jerry Koosman vs Bob Moose | First | -- |
| Friday, July 28 |
| » Defeated Mets (50-40), 3-1 | Three Rivers Stadium (32-18) | 57-34 | Won 2 |
| » Starters: Tom Seaver vs Dock Ellis | First | -- |
| Saturday, July 29 |
| » Lost to Phillies (34-58), 5-2 | Veteran's Stadium (1-2) | 57-35 | |
| » Starters: Steve Blass vs Woodie Fryman | First | -- |
| » Defeated Phillies (34-59), 3-2 | Veteran's Stadium (2-2) | 58-35 | |
| » Starters: Luke Walker vs Bucky Brandon | First | -- |
| Sunday, July 30 |
| » Defeated Phillies (34-60), 7-1 | Veteran's Stadium (3-2) | 59-35 | Won 2 |
| » Starters: Bruce Kison vs Barry Lersch | First | -- |
| Monday, July 31 |
| » Defeated Phillies (34-61), 2-0 | Veteran's Stadium (4-2) | 60-35 | Won 3 |
| » Starters: Bob Moose vs Ken Reynolds | First | -- |
| Former Pirate Rollie Hemsley dies in Washington, DC at the age of 66. |
| Tuesday, August 1 |
| » Lost to Cardinals (47-48), 7-4 | Busch Stadium II (2-2) | 60-36 | |
| » Starters: Nelson Briles vs Al Santorini | First | -- |
| Wednesday, August 2 |
| » Lost to Cardinals (48-48), 10-5 | Busch Stadium II (2-3) | 60-37 | Lost 2 |
| » Starters: Dock Ellis vs Bob Gibson | First | -- |
| Thursday, August 3 |
| » Defeated Cardinals (48-49), 2-1 | Busch Stadium II (3-3) | 61-37 | |
| » Starters: Steve Blass vs Rick Wise | First | -- |
| Friday, August 4 |
| » Lost to Expos (45-52), 2-1 | Parc Jarry (0-2) | 61-38 | |
| » Starters: Bruce Kison vs Balor Moore | First | -- |
| Saturday, August 5 |
| » Defeated Expos (45-53), 7-4 | Parc Jarry (1-2) | 62-38 | |
| » Starters: Nelson Briles vs Bill Stoneman | First | -- |
| Sunday, August 6 |
| » Defeated Expos (45-54), 8-0 | Parc Jarry (2-2) | 63-38 | Won 2 |
| » Starters: Bob Moose vs Mike Torrez | First | -- |
| » Defeated Expos (45-55), 7-2 | Parc Jarry (3-2) | 64-38 | Won 3 |
| » Starters: Bob Johnson vs Steve Renko | First | -- |
| Tuesday, August 8 |
| » Defeated Phillies (39-64), 4-2 | Three Rivers Stadium (33-18) | 65-38 | Won 4 |
| » Starters: Bill Champion vs Dock Ellis | First | -- |
| Wednesday, August 9 |
| » Lost to Phillies (40-64), 2-0 | Three Rivers Stadium (33-19) | 65-39 | |
| » Starters: Steve Carlton vs Steve Blass | First | -- |
| Friday, August 11 |
| » Defeated Cardinals (51-53), 10-5 | Three Rivers Stadium (34-19) | 66-39 | |
| » Starters: Reggie Cleveland vs Nelson Briles | First | -- |
| » Major-league debuts: Ron Allen (Cardinals) |
| Saturday, August 12 |
| » Defeated Cardinals (51-54), 6-5 | Three Rivers Stadium (35-19) | 67-39 | Won 2 |
| » Starters: Bob Gibson vs Bob Moose | First | -- |
| Sunday, August 13 |
| » Lost to Cardinals (52-54), 2-0 | Three Rivers Stadium (35-20) | 67-40 | |
| » Starters: Rick Wise vs Dock Ellis | First | -- |
| » Defeated Cardinals (52-55), 7-5 | Three Rivers Stadium (36-20) | 68-40 | |
| » Starters: Al Santorini vs Steve Blass | First | -- |
| Tuesday, August 15 |
| » Lost to Dodgers (58-50), 8-6 | Dodger Stadium (2-2) | 68-41 | |
| » Starters: Bruce Kison vs Claude Osteen | First | -- |
| Former Pirate Jeff Pfeffer dies in Chicago, IL at the age of 85. |
| Wednesday, August 16 |
| » Defeated Dodgers (58-51), 3-2 | Dodger Stadium (3-2) | 69-41 | |
| » Starters: Nelson Briles vs Don Sutton | First | -- |
| Thursday, August 17 |
| » Lost to Dodgers (59-51), 4-2 | Dodger Stadium (3-3) | 69-42 | |
| » Starters: Bob Moose vs Al Downing | First | -- |
| Friday, August 18 |
| » Defeated Padres (44-68), 4-2 | San Diego/Jack Murphy Stadium (4-0) | 70-42 | |
| » Starters: Steve Blass vs Bill Greif | First | -- |
| Sunday, August 20 |
| » Defeated Padres (44-69), 9-3 | San Diego/Jack Murphy Stadium (5-0) | 71-42 | Won 2 |
| » Starters: Dock Ellis vs Mike Caldwell | First | -- |
| » Defeated Padres (44-70), 5-2 | San Diego/Jack Murphy Stadium (6-0) | 72-42 | Won 3 |
| » Starters: Bruce Kison vs Fred Norman | First | -- |
| Tuesday, August 22 |
| » Defeated Giants (52-67), 1-0 | Candlestick Park (4-1) | 73-42 | Won 4 |
| » Starters: Nelson Briles vs Juan Marichal | First | -- |
| Wednesday, August 23 |
| » Lost to Giants (53-67), 8-0 | Candlestick Park (4-2) | 73-43 | |
| » Starters: Bob Moose vs Jim Barr | First | -- |
| Friday, August 25 |
| » Defeated Dodgers (62-55), 3-2 | Three Rivers Stadium (37-20) | 74-43 | |
| » Starters: Tommy John vs Steve Blass | First | -- |
| » Lost to Dodgers (63-55), 4-3 | Three Rivers Stadium (37-21) | 74-44 | |
| » Starters: Claude Osteen vs Bruce Kison | First | -- |
| Saturday, August 26 |
| » Lost to Dodgers (64-55), 7-3 | Three Rivers Stadium (37-22) | 74-45 | Lost 2 |
| » Starters: Don Sutton vs Dock Ellis | First | -- |
| Former Pirate Danny MacFayden dies in Brunswick, ME at the age of 68. |
| Sunday, August 27 |
| » Lost to Dodgers (65-55), 7-4 | Three Rivers Stadium (37-23) | 74-46 | Lost 3 |
| » Starters: Al Downing vs Nelson Briles | First | -- |
| Monday, August 28 |
| » Defeated Padres (46-76), 5-3 | Three Rivers Stadium (38-23) | 75-46 | |
| » Starters: Mike Caldwell vs Bob Moose | First | -- |
| Tuesday, August 29 |
| » Defeated Padres (46-77), 5-3 | Three Rivers Stadium (39-23) | 76-46 | Won 2 |
| » Starters: Mike Corkins vs Steve Blass | First | -- |
| Wednesday, August 30 |
| » Defeated Padres (46-78), 11-0 | Three Rivers Stadium (40-23) | 77-46 | Won 3 |
| » Starters: Steve Arlin vs Bruce Kison | First | -- |
| Friday, September 1 |
| » Defeated Giants (56-71), 10-6 | Three Rivers Stadium (41-23) | 78-46 | Won 4 |
| » Starters: Ron Bryant vs Dock Ellis | First | -- |
| Saturday, September 2 |
| » Defeated Giants (56-72), 6-3 | Three Rivers Stadium (42-23) | 79-46 | Won 5 |
| » Starters: Sam McDowell vs Nelson Briles | First | -- |
| Sunday, September 3 |
| » Defeated Giants (56-73), 2-1 | Three Rivers Stadium (43-23) | 80-46 | Won 6 |
| » Starters: Jim Barr vs Bob Moose | First | -- |
| Monday, September 4 |
| » Defeated Phillies (47-82), 10-0 | Three Rivers Stadium (44-23) | 81-46 | Won 7 |
| » Starters: Wayne Twitchell vs Steve Blass | First | -- |
| » Defeated Phillies (47-83), 5-1 | Three Rivers Stadium (45-23) | 82-46 | Won 8 |
| » Starters: Jim Nash vs Bruce Kison | First | -- |
| Tuesday, September 5 |
| » Major-league debuts: Hank Webb (Mets) |
| Wednesday, September 6 |
| » Defeated Cubs (71-61), 4-0 | Three Rivers Stadium (46-23) | 83-46 | Won 9 |
| » Starters: Dan McGinn vs Dock Ellis | First | -- |
| » Major-league debuts: Pete LaCock (Cubs) |
| Thursday, September 7 |
| » Lost to Cubs (72-61), 4-2 | Three Rivers Stadium (46-24) | 83-47 | |
| » Starters: Burt Hooton vs Nelson Briles | First | -- |
| Friday, September 8 |
| » Defeated Expos (61-70), 7-1 | Parc Jarry (4-2) | 84-47 | |
| » Starters: Bob Johnson vs Carl Morton | First | -- |
| » Defeated Expos (61-71), 4-2 | Parc Jarry (5-2) | 85-47 | Won 2 |
| » Starters: Bob Moose vs Ernie McAnally | First | -- |
| » Major-league debuts: Chuck Goggin (Pirates) |
| Saturday, September 9 |
| » Defeated Expos (61-72), 8-3 | Parc Jarry (6-2) | 86-47 | Won 3 |
| » Starters: Steve Blass vs Bill Stoneman | First | -- |
| Sunday, September 10 |
| » Lost to Expos (62-72), 8-2 | Parc Jarry (6-3) | 86-48 | |
| » Starters: Bruce Kison vs Mike Torrez | First | -- |
| Tuesday, September 12 |
| » Defeated Cubs (75-62), 7-0 | Wrigley Field (4-0) | 87-48 | |
| » Starters: Dock Ellis vs Burt Hooton | First | -- |
| Wednesday, September 13 |
| » Defeated Cubs (75-63), 6-4 | Wrigley Field (5-0) | 88-48 | Won 2 |
| » Starters: Nelson Briles vs Fergie Jenkins | First | -- |
| Thursday, September 14 |
| » Defeated Cubs (75-64), 5-2 | Wrigley Field (6-0) | 89-48 | Won 3 |
| » Starters: Bob Moose vs Rick Reuschel | First | -- |
| Friday, September 15 |
| » Lost to Cardinals (67-74), 10-4 | Busch Stadium II (3-4) | 89-49 | |
| » Starters: Bruce Kison vs Rick Wise | First | -- |
| » Major-league debuts: Fernando Gonzalez (Pirates) |
| Saturday, September 16 |
| » Lost to Cardinals (68-74), 4-0 | Busch Stadium II (3-5) | 89-50 | Lost 2 |
| » Starters: Steve Blass vs Al Santorini | First | -- |
| Sunday, September 17 |
| » Lost to Cardinals (69-74), 5-4 | Busch Stadium II (3-6) | 89-51 | Lost 3 |
| » Starters: Bob Johnson vs Reggie Cleveland | First | -- |
| Future Pirate Brian Smith is born in Salisbury, NC. |
| Monday, September 18 |
| » Lost to Mets (73-67), 1-0 | Shea Stadium (1-4) | 89-52 | Lost 4 |
| » Starters: Nelson Briles vs Jon Matlack | First | -- |
| Tuesday, September 19 |
| » Defeated Mets (73-68), 5-1 | Shea Stadium (2-4) | 90-52 | |
| » Starters: Bob Moose vs Jerry Koosman | First | -- |
| Wednesday, September 20 |
| » Lost to Mets (74-68), 4-1 | Shea Stadium (2-5) | 90-53 | |
| » Starters: Luke Walker vs Tom Seaver | First | -- |
| Thursday, September 21 |
| » Defeated Mets (74-69), 6-2 | Shea Stadium (3-5) | 91-53 | |
| » Starters: Steve Blass vs Gary Gentry | First | -- |
| » Major-league debuts: Joe Nolan (Mets) |
| Friday, September 22 |
| » Defeated Expos (65-79), 4-3 | Three Rivers Stadium (47-24) | 92-53 | Won 2 |
| » Starters: Balor Moore vs Bruce Kison | First | -- |
| Saturday, September 23 |
| » Lost to Expos (66-79), 3-0 | Three Rivers Stadium (47-25) | 92-54 | |
| » Starters: Ernie McAnally vs Nelson Briles | First | -- |
| Sunday, September 24 |
| » Lost to Expos (67-79), 2-1 | Three Rivers Stadium (47-26) | 92-55 | Lost 2 |
| » Starters: Carl Morton vs Bob Moose | First | -- |
| Tuesday, September 26 |
| » Defeated Phillies (55-93), 5-1 | Veteran's Stadium (5-2) | 93-55 | |
| » Starters: Steve Blass vs Wayne Twitchell | First | -- |
| Wednesday, September 27 |
| » Defeated Phillies (55-94), 3-1 | Veteran's Stadium (6-2) | 94-55 | Won 2 |
| » Starters: Bruce Kison vs Ken Reynolds | First | -- |
| Thursday, September 28 |
| » Lost to Phillies (56-94), 2-1 | Veteran's Stadium (6-3) | 94-56 | |
| » Starters: Bob Moose vs Steve Carlton | First | -- |
| Friday, September 29 |
| » Lost to Mets (78-71), 1-0 | Three Rivers Stadium (47-27) | 94-57 | Lost 2 |
| » Starters: Tom Seaver vs Nelson Briles | First | -- |
| Saturday, September 30 |
| » Defeated Mets (78-72), 5-0 | Three Rivers Stadium (48-27) | 95-57 | |
| » Starters: Jon Matlack vs Dock Ellis | First | -- |
| Sunday, October 1 |
| » Lost to Mets (79-72), 7-3 | Three Rivers Stadium (48-28) | 95-58 | |
| » Starters: Jerry Koosman vs Steve Blass | First | -- |
| Tuesday, October 3 |
| » Defeated Cardinals (74-81), 6-2 | Three Rivers Stadium (49-28) | 96-58 | |
| » Starters: Al Santorini vs Bob Moose | First | -- |
| Wednesday, October 4 |
| » Lost to Cardinals (75-81), 4-3 | Three Rivers Stadium (49-29) | 96-59 | |
| » Starters: Bob Gibson vs Nelson Briles | First | -- |
| Monday, October 16 |
| For |
