"He's day-to-day," Girardi said. "He just tweaked his groin a little bit. We could use him [on Sunday] if we have to."
Giambi injured the groin while rounding second base in the third inning on Saturday, and left the game two innings later. He received treatment during that game and again on Sunday morning, though Girardi said there was no reason to push his first baseman, especially considering Giambi's injury history. He has averaged just 110 games over the last four seasons due to a series of maladies.
Giambi is batting .083 on the season, with one double in 12 at-bats.
"He's feeling pretty good," Girardi said. "But maybe he overdid it a little bit."
Wilson Betemit played first base in Giambi's absence on Sunday, batting eighth.
Anthony DiComo is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.