Myers suffered the injury on a swing in the fifth inning of Saturday's victory over the New York Mets. He told The Athletic on Sunday that he expects to be sidelined for about 14 days.
Myers missed two weeks earlier this month because of nerve irritation in his right arm. He is batting .300 (12-for-40) with one home runs and three RBIs in 10 games this season.
The Padres recalled outfielder Travis Jankowski from Triple-A El Paso to replace Myers on the active roster.