Johnson caught manager Joe McCarthy’s attention in the Yankees’ wartime 1943 Asbury Park, New Jersey, training camp by taking infield practice while it was snowing. Johnson took over the Yankee third base job from Red Rolfe that season and had a great rookie year, hitting .280 with 94 RBI (third in the league) and leading AL third basemen in putouts, assists, and double plays. His bases-loaded triple in the eighth inning of Game Three of the 1943 WS overcame a 2-1 deficit to win the game. He spent 1944-45 in the military and had an off-year in 1946, but came back strong in 1947 to tie for fourth in the AL with 95 RBI. He set a record for a seven-game Series that fall with three triples; his four overall tied the lifetime WS record. He also led the Yankees with eight runs in the ’47 Series, twice as many as runner-up Joe DiMaggio.
In 1948 he hit a career-high .294 with 12 HR while leading AL third basemen in total chances per game, but dropped off in overall production. The arrival of Casey Stengel in 1949 cut into his playing time and his effectiveness, as Stengel platooned him with Bobby Brown, used him as a defensive replacement, and played him at first base. When Gil McDougald arrived in 1951, Johnson was traded in May to the Cardinals for Don Bollweg and $15,000. In his last full-time season, he led NL third basemen in fielding and hit a career-high 14 HR.