NEW YORK -- Beset by injuries all season, the New York Yankees entered new territory even for them on Friday night.

One at-bat into the game, they lost catcher Francisco Cervelli for at least six weeks with a fractured right hand that will require surgery.

Then, with no outs in the third, the other half of their starting battery, Ivan Nova, was forced to leave with elbow soreness. He underwent an MRI on Friday night, but the Yankees did not immediately have the results.

In the third inning, after a comeback single, Nova did not show any apparent signs of pain, but manager Joe Girardi and trainer Steve Donohue hopped out of the dugout right away and lifted him.

Prior to the third inning, Nova told Girardi and Donohue that the area just above his elbow, the triceps, was hurting him. He said he could try to pitch, so Girardi sent him out there.

After facing two batters in the inning, Girardi didn't think Nova looked exactly right.

"We went out there and asked him, and he said he wasn't OK," Girardi said.

Girardi was unsure if it was the triceps or the elbow causing Nova pain.

Nova was replaced by David Phelps. Phelps pitched well, going four innings and allowing one run on two hits while striking out nine to pick up the win in the Yankees' 6-4 victory. He's in position to go into the rotation if Nova is placed on the disabled list.

In Cervelli's absence, Chris Stewart is expected to become the Yankees' primary catcher. Yankees top prospect Austin Romine will be called up from Triple A on Saturday.

Cervelli will have surgery on Saturday.

Cervelli, whose hot bat and solid defense have made him the Yankees' primary catcher, injured his right hand on a foul ball from Toronto leadoff man Rajai Davis. Cervelli tried to stay in the game, but Girardi ultimately decided to replace him with Stewart.

Cervelli and Stewart had been fighting for the right to replace Russell Martin as the regular catcher. Girardi had chosen not to name either the starter yet, but Cervelli had played in 17 of the first 22 games. Stewart had appeared in eight.

Cervelli had started the season hitting .269 with three homers and eight RBIs. Stewart entered Friday hitting .333 in 31 less at-bats than Cervelli.

"It is disappointing for him because of all that he has been through," Girardi said.

Cervelli, 27, spent nearly all of 2012 in Triple-A after the Yankees traded for Stewart just before Opening Day to back up Martin. Cervelli looks like an improved player this season.

"Maybe all the work he did last year," Girardi said prior to the game when asked why Cervelli is such a better hitter. "He played winter ball this year. His desire to be an every-day player. It is not that he didn't have that desire before, but, at times, he was here and he wasn't playing every day. Last year, he got a chance to play every day [at Triple-A] and he got to play in winter ball. And, I think, as you get older, you improve because you get more at-bats under your belt. His at-bats have been really good."

Cervelli's name has appeared in the Biogenesis documents, according to reports. Cervelli admits to meeting with Biogenesis employees, but has denied taking any performance-enhancing drugs.

The Yankees have struggled with injuries all season. Derek Jeter and Alex Rodriguez are out until after the All-Star break, while Curtis Granderson and Mark Teixeira could make their 2013 debuts at some point in May.

If Nova is seriously hurt, the Yankees could replace him with Phelps, Adam Warren, Vidal Nuno or Chien-Ming Wang. Nuno and Wang are at Triple-A. If Phelps moves into the rotation, Warren could become the primary long man with reliever Cody Eppley, who is on the 40-man roster, being called up.

The Yankees could also move Jeter to the 60-day DL, which would open up a roster spot.