year and signed with the Oakland Oaks in the Pacific Coast League. His contract – along with Billy Martin's – was sold to the New York Yankees in with the intention of him being a backup for future Hall of Fame centerfielder Joe DiMaggio. But he played in only 108 games for the Yankees over three years, primarily in left field. He appeared as a pinch runner for Bobby Brown in the eighth inning of Game 3 of the 1950 World Series against the Philadelphia Phillies, but was in the game only briefly before Johnny Mize popped up to end the inning. Jensen did not stay in the game defensively, and the Yankees completed a sweep of the Phillies in Game 4. Mickey Mantle appeared in 1951 as DiMaggio's heir-apparent, preempting Jensen and starting in right field. Jensen did not appear in the 1951 Series against the New York Giants. In May 1952 Jensen was sent to the Washington Senators in a six-player deal, and he made his first All-Star team. He finished the season with a .286 batting average and 80 RBIs, leading the league with 17 assists and placing third in the AL with 18 steals, a total he duplicated in 1953. He was traded to the Red Sox in December 1953, and led the AL with 22 steals in , also finishing third in RBIs (117) and fourth in home runs (25). But despite his speed he also set a major league record by grounding into double plays 32 times, breaking fellow Red Sox Bobby Doerr's total of 31; the record would stand until Red Sock Jim Rice grounded into 36 double plays in . No longer facing the pressure of becoming his team's principal star, Jensen again made the All-Star team in , leading the league with 116 RBIs and finishing tenth in the MVP vote. In Jensen batted a career-high .315 and led the AL with 11 triples, and in he had 103 RBIs and led the league in both assists (16) and double plays (4). The 31 year-old star had his best season in , earning the AL MVP and beating out Bob Turley, Rocky Colavito and Bob Cerv with a .286 batting average, a league-leading 122 RBIs, also placing second in the AL with 99 walks and fifth in home runs (35), doubles (31), total bases (293) and on-base percentage (.396). In June