BALTIMORE -- Mark Teixeira will miss at least four games due to his injured left calf and won't return to the New York Yankees' lineup until Friday at the earliest.

Yankees manager Joe Girardi said Teixeira will have an MRI on Monday and acknowledged his concern that the star first baseman could be done for the rest of the regular season.

"There is part of me that wonders that," Girardi said of Teixeira's setback resulting in a prolonged absence. "There is basically 3.5 weeks left. If it does go back to square one, then I'd really wonder."

Teixeira was optimistic that he would play again this year.

"That would be the worse-, worse-case scenario," Teixeira said on the possibility of being done for the season.

Teixeira missed 10 games with the calf injury before starting Saturday night against the Baltimore Orioles. New York trailed by one run with runners on first and third and one out in the ninth inning when Teixeira busted it down the line to try to beat a game-ending double play.

Teixeira was called out, but replays clearly showed that his headfirst slide beat the relay throw.

"I think that is when he really felt it," Girardi said. "He talked about really feeling it. He busted his rear end to get down there. It is unfortunate."

After the 5-4 loss, Teixeira said he knew he had hurt the calf again. Teixeira also questioned the integrity of the umpires, saying that they might have made some calls because they wanted the game to end instead of a prolonged comeback. Teixeira said he expected to be fined for his comments.

"There is frustration," Girardi said. "I don't worry about that."

In Teixeira's absence, Girardi expects to shift Nick Swisher from right field to first base. Steve Pearce is expected to start occasionally against left-handed pitching. Swisher and Pearce both saw time at first during Sunday's 13-3 win against the Orioles.

Teixeira is tied with Curtis Granderson for the Yankees' team lead with 81 RBIs. He is batting .255 with 23 homers. The Yankees especially need Teixeira as a right-handed batter to balance out their lineups because of his .891 OPS against left-handed pitching.

"It is huge," Girardi said. "He is one of the guys that has been a middle of the order guy. He has been a big part of our lineup. He is an RBI guy."