FORT MYERS, Fla. (AP) — Closing in on his 39th birthday, Jason Varitek is warming to his role as a backup catcher. He’d like to keep playing well into his 40s.

The captain of the Boston Red Sox is set to begin a season as a second-stringer for the second time. He believes less wear on a body used to crouching for more than 100 pitches a night could extend his career.

“If my body holds up and I’m able to do the things that I feel that I can still do, then I’ll play as long as I can,” Varitek said Sunday. “If I’m not putting myself in a competitive spot to help a team win, then I’ve got to question things again.”

Injuries derailed three of his seasons — a fractured right elbow in 2001, cartilage damage in his left knee in 2006 and a broken right foot last year. He played in just 39 games in 2010, hitting .232 with seven homers and 16 RBIs as a backup to Victor Martinez. Now he’s playing behind Jarrod Saltalamacchia.

And, Varitek said, he’s healthier than he’s been in a long time.

“I don’t know how he does it, but he continues to do it every year,” manager Terry Francona said. “He works so hard. He’s in great shape. I think he’s going to excel in that (backup) role.”

It was thrust upon him when the Red Sox obtained Martinez from the Cleveland Indians at the trade deadline on July 31, 2009. At midseason, Varitek suddenly found himself on the bench.

But he started last season as Martinez’s substitute and that helped him become more comfortable with the role. It gave him a chance to spend more time learning through observation.

“It allows me, like last year, to be a little more attentive to things that are going on by not playing,” Varitek said. “You see a little more rather than being caught up in just getting ready to play.”

Varitek, who turns 39 on April 11, received what many interpreted as a farewell from Red Sox fans in the final game last season. He took the field in the bottom of the ninth inning of an 8-4 win over the New York Yankees then was removed by Francona before the first pitch.

Fenway Park fans gave him a standing ovation.

“It was very uncertain,” Varitek said. “It presented (me) with an emotional time, but, at that point, it was out of my control. … I knew I had a good chance where I could help a team and, hopefully, it was going to be here. And it turned out to be that way.”

He went into the offseason as a free agent. So did Martinez. If the Red Sox kept Martinez, Varitek’s future with them appeared to be shaky. But Martinez signed with the Detroit Tigers on Nov. 24 and Varitek signed a $2 million, one-year deal with Boston eight days later.

“When we took him out of last year’s game, the last game, to get a little bit of an ovation, everybody made a big deal out of it,” Francona said. “We do that with a lot of the veterans. It wasn’t a goodbye. It was just a chance for everybody to show their appreciation.”

It wasn’t the first time Varitek’s tenure with the Red Sox was in question.

After they won the World Series in 2004, he became a free agent but ended up re-signing with them for four years and $40 million. He was a free agent again after the 2008 season and returned for $5 million, then picked up his $3 million player option for 2010.

Now he’s back after an offseason in which he began training earlier than normal, perhaps because he played so little.

“I’ve kind of always had a barometer,” Varitek said. “When I’d walk down stairs straight I knew I was ready to start training. If I was still going down sidewise, I had to wait a little longer. … After a couple weeks I was ready to go.”

Varitek is entering his 14th season since being obtained in one of the most one-sided trades in club history with Derek Lowe from the Seattle Mariners for reliever Heathcliff Slocumb on July 31, 1997.

Varitek had just one at bat that season, a pinch-hit single in a 9-2 win at Detroit on Sept. 24, 1997. Tim Wakefield, who got the win in that game, is one of three other players on that Boston team still in the majors. The others are pitchers Lowe and Jeff Suppan.

He was a three-time All-Star before struggling with batting averages of .220 in 2008 and .209 in 2009. Then came his lost 2010 season.

So why does Varitek keep coming back?

“Why not?” he said. “You can only play this game for so long and as long as your body holds out and you can be productive and do things, I love playing.”

He doesn’t figure to play a lot unless Saltalamacchia, 25, gets hurt or struggles in what would be his first full season.

“He’s going to be a good player,” Varitek said. “He’s too gifted and works too hard not to be.”

And Varitek, known for his leadership, attention to detail and handling of pitchers, could be a manager someday.

“I’m worried enough about playing right now,” he said. “We’ll talk about that later.”