Both players were disabled retroactively, with right-hander Chris Britton joining the club from Triple-A Scranton/Wilkes-Barre to help a staff that entered Sunday having played two consecutive extra-inning games at Oakland.
The Yankees have announced that Double-A left-hander Chase Wright -- who leads the Eastern League with 19 strikeouts in 14 scoreless innings and is already on the 40-man roster -- will be recalled in time to start on Tuesday against the Indians, making a start that was envisioned to go to Pavano.
Mussina strained his left hamstring in the third inning of his appearance on Wednesday at Minnesota, and Pavano was scratched from a scheduled start Saturday due to stiffness in his right forearm.
The hurlers join a corps of walking wounded that includes right-handers Chien-Ming Wang and Jeff Karstens, who were expected to be members of the Yankees' starting rotation but suffered injuries in Spring Training and have not yet pitched in the Majors this season.
"You just find a way to get through it and deal with these things," Mussina said. "It's unfortunate, but you have to deal with what you have to deal with. Nobody's having surgery, nobody's out for three months. Nobody's having a situation like that. It's a couple of muscle pulls and a strain. It'll be fine."
The rash of injuries are especially striking because they involve Pavano, who missed the last 1 1/2 Major League seasons before finally progressing through Spring Training healthy and making two starts for New York this season.
"For one reason or another, these things happen," Pavano said. "I've been through this before. I've just got to keep working. We're going to get on top of this, and we'll do what it takes. I'm going to get back out there."
Pavano said that his right forearm began to tighten up in the final two innings of his start at the Metrodome on Wednesday, when he logged his first Major League victory since May 2005.
He suspects that one of the sidearm throws he made in the contest -- one on a double play of Joe Mauer in the first inning, and another on a pickoff throw to first base -- could have caused a strain in the muscular area between his elbow and forearm.
Pavano had been slated to pitch on Saturday at Oakland, but he was pushed back to allow the stiffness time to clear up, with an effort for Tuesday against the Indians in New York targeted. But with Pavano still reporting issues as of Saturday, the Yankees will need to find another starting pitcher for that contest.
"It's not where I want to be and not where I need to be," Pavano said. "It just doesn't feel good. It doesn't feel good to have a time like this when guys are going down. I need to be part of the staff, but it's not something that's going to get any better by going out there and trying to be a hero."
Both Mussina and Pavano tested their respective injuries early Sunday at McAfee Coliseum, but neither was pleased with the results each received.
Mussina performed some light running and briefly attempted to throw off a mound, but he stopped himself; Pavano performed long-toss and never even took the bullpen rubber, concerned that revving up his pitch velocity might cause further discomfort to what he believes is a muscular issue.
"I was going to take a shot and just go out there, and see if I got up on the mound and it loosened up," Pavano said. "It hasn't been responding the last three or four days the way I'd like it. Sometimes, a little bit more time would have taken care of that, and we gave it that little bit extra time. It's just not good enough."
Mussina said that he is able to play catch and throw, and all things considered, he believes his situation could have been a lot worse just four days after suffering the initial injury.
As a right-hander, the left leg affects Mussina's ability to stop, as he delivers on the mound's downward plane. Mussina said that if the situation progresses as much in the next four days as it did in the previous four, he would be in good shape.
"It's smarter to get rid of it and then go pitch," Mussina said. "We'll take our time and go do it right. If I can improve this much in the next four days, I'll feel pretty good.
"I don't want to come back to the beginning. I've made a lot of improvements. I don't want to start over."
The Yankees' rotation picture might begin to appear a little brighter in the coming days, as Wang moves closer to rejoining the Major League club.
Wang pitched five scoreless, hitless innings in an extended Spring Training game against the Devil Rays on Saturday and is scheduled to pitch for Class A Tampa on Thursday in a Florida State League contest. After that point, the Yankees will consider activating Wang, who suffered a strained right hamstring while performing conditioning drills on March 23.
Bryan Hoch is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.