After his four-year coaching stint at Yale, Rolfe coached the Toronto Huskies of the BAA in 1946-1947 and returned to the Yankees as a coach. After the 1947 season, Rolfe joined the Detroit Tigers as director of their farm system. But he returned to the field after only one season, when he succeeded Steve O'Neill as Tiger manager after the 1948 campaign.
In 1949, Rolfe's first season as manager, the Tigers improved by nine games and returned to the first division. Then, in 1950, they nearly upset the Yankees, winning 95 games and finishing second, three games behind. A fluke botched double play was the team's undoing. Late in September at Cleveland, the Indians had the bases loaded in the tenth inning with one out and the score tied. Visibility was poor because smoke from Canadian forest fires was blowing across Lake Erie. On an apparent 3-2-3 double-play grounder to first base, Detroit catcherAaron Robinson thought he simply needed to touch home plate for a force play to retire the Indians baserunner charging in from third. But in the smoky conditions Robinson had not seen that a putout had already been made at first base, necessitating that the catcher tag the runner, not the plate, to record an out. Robinson mistakenly tagged the plate, the run counted and Cleveland won the game. It was the turning point in the pennant race, for the postwar Tigers, and for Rolfe's managerial career.
Beset by an aging starting rotation, the Tigers faltered in 1951, slipping to 73 wins and finishing fifth, 25 games behind New York. Then Detroit completely unraveled in 1952, winning only 23 of 72 games under Rolfe. On July 5, he was fired and replaced by one of his pitchers, Fred Hutchinson. The 1952 club won only 50 games, losing 104 – the first time ever that the Tigers lost 100 or more games.
Rolfe then returned to Dartmouth as the athletic director of his alma mater from 1954–1967. The college's baseball diamond is named in his honor. Rolfe died at Gilford, New Hampshire, in 1969 at age 60 from chronic colitis.