After trouble finding another suitable opponent, on December 5, 1947, Joe Louis met Jersey Joe Walcott, a 33-year-old veteran with a 44–11–2 record. Walcott entered the fight as a 10-to-1 underdog. Nevertheless, Walcott knocked down Louis twice in the first four rounds. Most observers in Madison Square Garden felt Walcott dominated the 15-round fight. When Louis was declared the winner in a split decision, the crowd booed.
Louis was under no delusion about the state of his boxing skills, yet he was too embarrassed to quit after the Walcott fight. Determined to win and retire with his title intact, Louis signed on for a rematch. On June 25, 1948, about 42,000 people came to Yankee Stadium to see the aging champion, who weighed 213½, the heaviest of his career to date. Walcott knocked Louis down in the third round, but Louis survived to knock out Walcott in the eleventh.
Louis would not defend his title again before announcing his retirement from boxing on March 1, 1949. In his bouts with Conn and Walcott, it had become apparent that Louis was no longer the fighter he once had been. As he had done earlier in his career, however, Louis would continue to appear in numerous exhibition matches worldwide.