Gibbs spent his four first professional seasons in minor league baseball, where his highest season batting average was .284 and he managed to hit 28 home runs across the four seasons. With Yogi Berra's retirement before the 1964 season, Gibbs competed for a spot on the Yankees' roster. He was unable to appear in the 1964 World Series due to broken fingers. He also missed the end of the 1966 season after suffering a broken left hand. Gibbs backed up Elston Howard for a number of years. When the Yankees traded Howard during the 1967 season, Gibbs became the team's starting catcher. He eventually lost the first-string job to Thurman Munson, but continued as a back-up with the team. In June 1971, he announced his retirement from baseball, effective at the end of the season. He played his final game on September 29, 1971.