"I expect it to clear up," Girardi said. "I don't know if I'll have him tomorrow either."
Headley has dealt with lower back problems before; Girardi said the current spasms could be a recurrence of previous ailments.
Headley is batting .245 with a .697 OPS in 64 games. He had a rough month of May but has picked up his play since the start of June. He's currently riding a 15-game on-base streak, during which he has a .444 OBP.
Headley was not available for comment after the game.
Matthew Martell is a reporter for MLB.com based in New York.