O'Neill was a righthander on the 1939 St. Mary's College Pacific College Conference champions, coached by former major leaguer Earl Sheely (NLM)

FROM THE BASEBALL CHRONOLOGY » May 27, 1945: The White Sox get only three hits total in a doubleheader loss to the Red Sox. Boo Ferriss allows only a single —by Tony Cuccinello in the 2nd—in the opener to win, 7–0, for his 6th straight victory and 4th shutout. Emmett O'Neill gives up two singles in the nitecap to win, 2–1. » May 26, 1946: The Red Sox turn stingy as Boo Ferriss holds the White Sox to one hit in the opener of two. In the nitecap, Emmett O'Neill allows just two Chicago hits. The three hits allowed in a doubleheader equals the 1934 record set by the Dean brothers, when Paul Dean tossed a no-hitter in game 2.