TAMPA, Fla. -- The Yankees promise that when Opening Day arrives, Jesus Montero and Austin Romine will be strapping on their catching gear to continue their climb toward a career in the big leagues.

They just aren't sure who will be where. Both catching prospects remain in the unsettled mix, as the Yankees attempt to figure out who is their best fit as the backup backstop to Russell Martin.

"It's still something that we're trying to sort out," Yankees manager Joe Girardi said. "We're just going to let that play out."

Montero, a touted power hitter, will be back behind the plate on Monday evening, as the Yankees try to solve another of their spring dilemmas in looking for positive signs from fifth-starter candidate Bartolo Colon.

Colon may steal the attention, but there will be focus on Montero as well, as the 6-foot-3, 21-year-old looks to prove that he is capable of handling a roster spot the Yankees say will be weighed for defense first, offense second.

"My goal this year is to get to the big leagues, be on the team and help the pitchers and the regular catcher," Montero said. "That's what I'm thinking this year."

With last year's understudy, Francisco Cervelli, sidelined with a broken left foot, Montero has received more opportunities to impress than Romine, a 22-year-old who has not played above Double-A.

But with Montero batting just .212 (7-for-33) to Romine's .167 (4-for-18), the Yankees haven't been gifted with a slam-dunk call to make. Montero may have slugged 21 homers last year at Triple-A Scranton/Wilkes-Barre, but the perception is still that Romine is the superior performer behind the plate.

"Romine has been considered a better defensive catcher than Montero," Girardi said. "I've seen Montero make great strides. I believe that he has definitely closed that gap."

Girardi said that Montero has made better throws to second base and blocked balls better than in previous camps and is leaps and bounds ahead of where he was at this time last spring.

"We've been saying Montero is going to be a catcher in the big leagues, and I think now people are beginning to say, 'Wow, he really is improved,'" Yankees general manager Brian Cashman said. "It's nice to see that people are recognizing it."

Cashman added that the Yankees have actually rated Montero ahead of some big league catchers, defensively -- food for thought to those who believe Montero may be more Carlos Delgado than Mike Piazza.

However, Romine wields a big league pedigree -- he's the son of former Red Sox outfielder Kevin Romine -- and has the defensive acumen to duplicate what Cervelli provided for Yankees hurlers over the last couple of years.

"My catching has come a long way," Romine said. "If you would have asked me three years ago if I was going to be in the big leagues -- I had eight passed balls a game and didn't really know what I was doing.

"The strides I've made behind the plate and the consistency I've shown back there have spoken volumes, to let me feel more comfortable catching bigger-name pitchers and proven veterans."

A former catcher himself, Girardi said that he has been in the ears of both backstops. Last week, Girardi said he spotted a flaw in Romine's game, but wouldn't divulge it to reporters, in case other teams might be listening.

"Romine joked about it yesterday; he said, 'I knew you had me,'" Girardi said. "And I said, 'Yeah, I've got you.' There are little things as a catcher you need to do that I stay on them both [about]."

A second-round pick of the Yankees in 2007, there has long been a perception that Romine could have a bright big league future ahead, but he does not want to run the risk of jeopardizing it.

That was apparent last season, when Romine and some friends visited New York City on an off-day for the Trenton Thunder.

Romine made it as far as the doorstep of Yankee Stadium, peeking inside to see batting practice displayed on the many LCD screens.

Still, he dared not try to enter the building, preferring instead to wait until he is invited to wear a uniform in a big league stadium.

"I just didn't want to jinx it," Romine shrugged.

The one caveat the Yankees have regarding Romine's game is not that he hasn't played above Double-A -- neither had Cervelli when he joined the Yanks or, for that matter, Girardi, when he made the '89 Cubs roster out of spring.

"A lot of guys have gone from Double-A to the big leagues," Romine said. "It's good ball down there as well. I don't really see it as a disadvantage."

The Yankees were concerned, however, that Romine seemed to grow fatigued in the second half last year at Trenton. But that does little to diminish their enthusiasm.

"He could have caught in the big leagues last year," Cashman said. "He's like Cervelli -- [when he was] in the Florida State League, Cervelli could have caught in the big leagues. Romine was the same way."

Girardi has said that the Yankees do not necessarily need to decide their backup catcher until March 28, but as with their rotation, it is likely that the final call will be made before then.

With Martin finally healthy and beginning to see the whole pitching staff, the last 1 1/2 weeks of camp promise to offer the Yankees opportunities to confirm -- or reverse -- their opinions of the catching prospects.

"The defense is important, and we need to continue to see that from both of them, that they can possibly handle this situation," Girardi said.