"We're not scheduling, but we're tentatively looking at possibly next weekend," Yankees manager Joe Torre said.
Clemens, 44, met with team medical staff Sunday in Tampa, Fla., and has been scheduled for an MRI so the Yankees can better determine the right-hander's physical state.
As of right now, all the club has been able to go on is Clemens' self-diagnosis from Friday, when he buzzed general manager Brian Cashman's cell phone from Houston and reported that he would not be able to pitch on Monday at Chicago due to a "fatigued groin."
"This man knows what he can and can't do from past experiences," Cashman said. "Apparently he was feeling a little something and didn't think it was a big deal. Yesterday, it was still there, and that's when he decided [he] couldn't do this."
Clemens is believed to have tweaked a groin muscle during the first inning of his start last week for Triple-A Scranton/Wilkes-Barre, and the club has speculated Clemens reaggravated it during a bullpen session at Yankee Stadium last Wednesday.
Cashman said that Clemens will remain in Tampa as he works his way toward starting the clock on the prorated $28 million, one-year deal he signed with the Yankees on May 6. Cashman described the hurler as "optimistic" that his recovery would not take long.
The possibility of groin injuries was a risk the team was willing to accept when they entered into the agreement to bring Clemens, who pitched for the Yankees from 1999-2003, back to the Bronx, Cashman said.
"This is something that is the reality of Roger," Cashman said. "Throughout his career, he's had a lot of injuries there in the groin. Historically, he gets through it. He knows his body and this is part of him."
Torre said he had no qualms about counting on the soon to be 45-year-old Rocket to be a productive member of the Yankees' rotation.
"I know he's getting up there in age and all that stuff," Torre said. "Knock on wood, the only issues he's had have been with the lower half of his body. That's pretty good."
Because Clemens is on a Minor League contract, Cashman said that no part of Clemens' contract is guaranteed, nor do the Yankees have a set date on which they must add the seven-time Cy Young Award winner to their roster.
But Cashman rejected the suggestion that the Yankees might decide to part ways with Clemens given their sizable deficit in the American League East - just 5 1/2 games on the day Clemens signed, the gap between the Yankees and the division-leading Red Sox had swelled to 13 1/2 games entering play Sunday.
"I want to have a healthy Roger Clemens, when he's ready, to assist this team because we still have a shot," Cashman said. "We're in this thing, we're not out of it. He can make an impact for us."
Bryan Hoch is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.