Manager Bud Black said Hairston hurt himself running in to catch a line drive off the bat of Dodgers infielder Blake DeWitt, although Hairston did stay in the game.
"He has a little bit of a nagging hamstring," Black said prior to Sunday's series finale with the Dodgers. "It occurred [Saturday]."
Black also said he will stay away from Hairston as a pinch-hitter despite the presence of a few left-handers in the Dodgers' bullpen. The severity of the injury or how long it might affect Hairston's status is unknown.
"We don't know," Black said. "Those are hard to gauge sometimes." Kyle Blanks, Tony Gwynn, and Will Venable were the starting outfielders on Sunday with Hairston out.