Injury update: Pettitte, Stewart, and more.

Pettitte hopes for nothing serious:

Andy Pettitte left in the 5th inning of Thursday's 3-2 lose to the Mariners, with tightness in his left trap muscle. Yankees manager Joe Girardi said after the game that he believes it's nothing serious.

"I don't think Andy's [injury] is too bad," Girardi said. "His trap just kind of got a knot in it, and to me it was affecting his velocity. That's why I took him out. It's muscular, but I don't know what that means going forward." 

After striking out Kyle Seager for the 2nd out of the 5th inning, Girardi and trainers ran out to check on Pettitte. Trying to state his case of staying in the game, Pettitte was forced out after 79 pitches.

"Obviously, I'm realistic," Pettitte said. "I know how these guys are. I asked them if I could stay out there and try to get through it out there. I'm hoping it's a spasm and it settles down."

Girardi said that the tightness was effecting Pettitte's velocity, so thats why they wanted to remove him from the game.

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

It Pettitte isn't able to make his next scheduled start, then the Yankees will consider placing him on the DL.

"He feels OK today," Girardi said. "We don't necessarily need to make a decision right now, what we're gonna do. His start wouldn't be for a few days. So we'll just continue talking about it."

Stewart may possibly meet the DL:

Pettitte wasn't the only Yankee to leave last nights game because of injury. Chris Stewart was also forced to leave after the 7th inning when he had some trouble coming into 3rd base. Stewart finished the inning but was replaced to Austin Romine to start the 8th.

Stewart was sent to undergo an MRI after the game on his left groin, according to Joe Girardi.

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

The good news is that the MRI came back clean and Stewart believes he should only be out for a few games. 

"Walking's fine. It's just running, when I push off, it's still there a little bit," Stewart said. "So, give it a couple of days, and then hopefully (I'll) be back out there."

"If [Stewart] wasn't a player at all, that would be an issue. But he could catch if we needed him to," Girardi said, adding that infielder Alberto Gonzalez also could play behind the plate if necessary."

Other injury notes:

* Joba Chamberlain was eligible to come off the DL yesterday, but according to Girardi he wasn't ready yet. 

"We're going to have him throw again," Girardi said. "Our concern is that he's just not quite ready yet. I think he's going to play catch again [Thursday], and then I'm not sure what the next step will be, whether it will be another bullpen or he will go on another rehab assignment."

* Travis Hafner took BP at Yankee Stadium on Thursday and feels encouraged he'll be back in action soon.

"Everything went really well," Hafner said. "I didn't have any of the issues I had before. I'm really happy with how it went."

"I'm really encouraged by today," Hafner said. "Hopefully I'll be back out there soon."

For more Yankees injuries updates, check back here and follow @GavinEwbank2013 on Twitter.