Signed out of Southern University for a $30,000 bonus in 1961, Brock moved up to the Cubs within one season. He hit only .263 and .258 in two full seasons with Chicago while showing flashes of both speed and power, including a 450-foot home run into the centerfield bleachers at the Polo Grounds, one of only four homers ever to land there. He came into his own after moving to St. Louis in a six-man trade on June 15, 1964. The deal was essentially Brock for pitcher Ernie Broglio, and is regarded as one of the worst the Cubs ever made. Brock averaged .348 in the 1964 stretch drive and finished the season at .315, with 111 runs scored, 200 hits, 30 doubles, 11 triples, and 43 stolen bases. In fourth place when Brock joined them, the Cardinals overtook the Phillies, Giants, and Reds to claim the pennant in the last week of the season. Brock then batted .300 with a homer as the Cardinals beat the Yankees in the World Series. He scored 107 runs and stole 63 bases in 1965, then won his first of four straight and eight total stolen-base championships with 74 in 1966. Brock's greatest season was probably 1967, when he led the Cardinals to another World Championship with a league-leading 113 runs scored, 52 steals, and career highs of 21 homers, 76 RBI, and a .472 slugging average. Brock batted .414 with seven steals against Boston in the WS, breaking or tying four Series records. Although he slumped to .279 in 1968, Brock helped St. Louis win the pennant again by leading the NL in doubles (46) and triples (14) as well as steals (62). The Cardinals lost the World Series to the Tigers in seven games, but Brock was sensational. He hit .464 to lead both clubs, with two homers and seven steals. At that time he had the highest average (.391) of any player in two or more World Series, along with a Series-record 14 steals. His .655 slugging average ranked fifth and his seven doubles ranked eighth. Brock hit between .297 and .313 in each season from 1969 through 1976 and led the NL with 126 runs in 1971. Former teammate Bobby Tolan edged Brock, 57 to 51, for the 1970 stolen- base championship, but Brock then won four more titles in a row with 64, 63, 70 and 118. Brock's 118 steals in 1974 shattered Maury Wills's major league record of 104, set in 1962, and remains the National league record through the 1980s (Rickey Henderson broke the ML record with 130 in 1982). At 35, Brock was by far the oldest man to steal 100 bases. "I figured it was now or never," he said.
He dropped off to "only" 56 steals in each of the next two seasons. Dipping to .221 and 17 steals in 1978, Brock lost his regular job and was urged to retire. Instead he rebounded to .304 with 21 steals, retiring first all-time in stolen bases with 938. He was elected to the Hall of Fame in 1985, his first year of eligibility. Despite Brock's high averages and electrifying feats on the bases, his stature is disputed by baseball experts. He struck out over 100 times in nine seasons, over 90 times in 12 seasons, and fanned more often than he scored in 11 seasons. He also struck out 1,730 times career, the most all-time at his retirement, while walking only 761 times, a poor ratio for any player and horrendous for a leadoff man. Brock also led the NL in errors seven times, including five years consecutively, never committing fewer than 10 from 1964 through 1973. He was shifted from centerfield to right before settling in left in 1966, primarily because of his defensive shortcomings. (MC