On july 1, 1948 Brooklyn’s Roy Campanella makes his debut, catching Ralph Branca. Campy doubles in his first at-bat, adds two singles, but the Giants win 6 – 4 over Branca.

Roy Campanella, who began the year with the Brooklyn Dodgers, is shown here during his brief stint with the 1948 St. Paul Saints. The 26-year-old backstop became the first black player in American Association history, and also put on quite show, slashing .325/.432/.715 with 13 homers and 39 RBI in only 35 games before rejoining the Dodgers in July. Though usually referred to as one of Brooklyn’s most promising young players, Campy had, in fact, been starring on professional diamonds for over a decade, having begun his career as a 15-year-old in the Negro National League.

In an interview with The Sporting News in August 1948, Campanella’s father, John, described his son’s lifelong passion for the sport: “Roy’s heart was set on baseball when he was too small to swing a bat. First, they let him be water boy, then bat boy, and when he got his first uniform—well, that was just plain heaven to him.” Campy’s obsession with baseball would pay off in 1937 when he joined the Baltimore Elite Giants of Negro National League. Originally signed to give future Hall of Famer Biz Mackey the weekends off, by 1941 the youngster was garnering comparisons to Josh Gibson. That year, Campy slashed .337/.408/.620 and took home MVP honors in the East-West All-Star Game.

Following a two-year stretch (1944-45) that saw him hit .382, Campanella drew the attention of Branch Rickey, who signed the phenom to play for the Nashua Dodgers of the New England League. Campy, who had been making $600 a month in the Negro Leagues, wasn’t thrilled with his contract which called for a $185 monthly salary. The 24-year-old backstop, described by The Sporting News as “a powerful-muscled, rather squat, brown-skinned Negro,” hit .290 with 13 HRs and was named league MVP in 1946. Having conquered the league, Campanella played with the Montreal Dodgers (AAA) in 1947, hitting .273 with 13 HRs and 73 RBI. It was around this time that Campy received a visit, at Rickey’s request, from Jackie Robinson; the pair reminisced about their first meeting in 1945. “Jackie made things easy for us,” said Campanella years later. “Because of him, I’m just another guy playing baseball.

Source
Baseball Reference July 1