Andy Pettitte, Chris Stewart hurt

NEW YORK -- New York Yankees left-hander Andy Pettitte left Thursday night's 3-2 loss to the Seattle Mariners in the fifth inning with tightness in his left trapezius muscle, which is located in the upper shoulder/back area.

Catcher Chris Stewart also departed the game with a left groin injury after running the bases in the seventh inning. Stewart went for an MRI after the game, and there was no immediate word on its result.

After the game, Pettitte said his trap muscle wasn't tight anymore and he wasn't hurting. He isn't sure if he'll have to miss his next scheduled start, on May 21 at Baltimore. The team doctor told Pettitte he believes it was just a spasm.

"I'm realistic, I know how these guys are. I asked them if I could stay out there and try to get through it," Pettitte said. "I'm hoping it's a spasm and it settles down. I know my back didn't loosen up [on the mound]. I can't tell you I've had this before; I haven't. But I don't feel it tight right now. I feel like it's loosened up and relaxed. I would think that's a good sign."

The 40-year-old pitcher said he first started feeling his trap muscle flare up after the top of the fourth inning, describing that it locked up on him. It calmed down after a quick massage and some heat therapy, but it locked up on him after throwing the first pitch of the inning to Jason Bay, whom Pettitte struck out.

"I couldn't get extended at all," Pettitte said. "Felt like I was cutting everything off and really trying to throw it in there almost slower than slow, to tell you the truth."

After Pettitte struck out Seattle's Kyle Seager on a 77-mph slider for the second out of the fifth inning, Yankees manager Joe Girardi, pitching coach Larry Rothschild and trainer Mark Littlefield all visited him on the mound. After a brief meeting, which included Pettitte trying to talk his way into staying in the game, Pettitte left the game after throwing just 79 pitches and the Yankees trailing, 2-1.

Pettitte gave up four hits, struck out five and was tagged with the loss. Girardi said the drop in Pettitte's velocity concerned him, and that led to taking the veteran out of the game. The 79 pitches were a season-low for Pettitte.

"I don't think Andy is too bad," Girardi said. "His trap kind of got a knot in it and affected his velocity, and that's why I took him out."

Pettitte previously dealt with back spasms in April, which caused a scheduled start to be pushed back twice. The veteran has struggled with injuries the past few years; he last made a full season's worth of starts in 2009. He made only 21 starts in 2010, and after returning from his retirement, he made only 12 starts in 2012 due to a broken left fibula.

Pettitte is 4-3 with a 3.83 ERA in eight starts this year.

"He is 40 years old and we're probably going to go through this a little bit," Girardi said.

Stewart left the game after running the bases in the seventh inning. After he reached third on an infield single by Robinson Cano, Girardi and trainer Steve Donahue checked on the catcher during a pitching change. Stewart stayed in the game, but was replaced by backup Austin Romine between innings.

Stewart has been the team's everyday catcher with Francisco Cervelli on the disabled list. Stewart went 1-for-2 on Thursday.

"When he went around the base and stopped, he felt something," Girardi said. "He said it didn't pop and he said he was OK, and when we saw him run, it continued to hurt, and we said, 'Well, we got to get you out.'"

Girardi said the team will wait to see the MRI results before making any determination on what to do with Stewart. If he's unavailable for any period of time, the team will all but certainly make a move to have a backup catcher in case of an emergency. Romine, who would be the starter, is hitting just .063 in 16 at-bats.

If Pettitte has to miss time, the Yankees could turn to Adam Warren, who is a long reliever in the team's bullpen. Warren pitched a scoreless ninth inning Thursday and is now 1-0 with a 1.37 ERA spanning 19 2/3 innings. He has appeared in eight games and has yet to make a start this year, though he was a starter in the minor leagues. He has struck out 15 and given up 15 hits.

The injuries to Pettitte and Stewart are the latest to an already injury-riddled roster.

The Yankees are already without shortstop Derek Jeter (ankle), third baseman Alex Rodriguez (hip), first baseman Mark Teixeira (wrist), catcher Francisco Cervelli (hand), third baseman Kevin Youkilis (back) and starter Ivan Nova (triceps), among others.

"You got to move forward, that's the bottom line," Girardi said. "Injuries are part of the game. Some years you are going to have more than others. Right now we have a few and you have to move on. There's no excuses. You got to find a way to get it done."