Red Sox starter Curt Schilling pitches in the first inning last night. Schilling left in the eighth inning with the Sox trailing 4-1 after giving up a three-run home to Derek Jeter.

The Providence Journal / Glenn Osmundson

BOSTON — He’s the captain. He’s the leader.

Jason Varitek may wear a “C” on his jersey, but it should really be an “I” for indispensable.

The Boston Red Sox learned that firsthand in August of last year, when Varitek was limited to 103 games for the season and required surgery on his left knee to repair torn cartilage. The Sox have always known how important Varitek is to the club, on and off the field.

That point hasn’t been so noticeable than it was this week.

After the Red Sox lost to the Yankees Friday night, Varitek was at his locker once again, answering questions for a bullpen that allowed New York to come back from a 7-2 deficit in the eighth inning.

It may be tough for fans to miss the fact that he entered last night’s game hitless in his last 15 plate appearances, while hitting just .083 in his last seven games. Those numbers are tough to ignore. Another number that can’t be ignored is the 112 games behind the plate, and because of that work load, he’s hitting a lowly .253 with 13 homers and 62 RBI.

“Any catcher in this league — you’re going to lose at-bats if you care enough about catching,” said Red Sox manager Terry Francona. “There are times when Jason will come off the field and he’s leading off the inning, and he’s got a pitcher corralled next to him, so he’s running up to his at-bat. At other positions you can think about your at-bat a little bit. … You want your catcher to do exactly what Jason does and care about running the game, but it has to cost you offensively at some point.”

The Red Sox players don’t feel they’re losing out in any aspect.

“He’s awesome,” said Red Sox pitcher Josh Beckett. “There’s a reason he wears that C on his jersey. He’s our captain and he leads on and off the field with everything he does. He’s a consummate professional and does things the right way.”

Beckett has been a teammate of Varitek’s for only two seasons, but David Ortiz probably knows better than anyone in the Red Sox clubhouse just how important Varitek is.

“Man, el capitan, he’s a leader, man,” Ortiz said. “He’s a guy who knows how to deal with situations better than anyone around here, I can tell you that. He’s great. He doesn’t talk too much, but when he sees things going in the wrong direction, he tries to fix them up.”

When reliever Eric Gagne arrived in Boston after it acquired him at the trade deadline, Varitek immediately introduced himself and the two hit it off. Gagne said he was impressed with the fact that his new batterymate already did his homework and knew exactly what kind of pitcher he would be working with.

Gagne, a nine-year pro, has worked with a lot of catchers, but he hasn’t dealt with another catcher quite like Varitek.

“I don’t think so,” he said. “The guy is always prepared. He does more and more everyday. Every time he gives up a run, he takes it personally. He takes it as his own ERA, and that’s what makes him so different.”

Varitek spends just as much time with the young guys as he would with a veteran such as Curt Schilling.

“He’s great,” Jon Lester said. “He’s probably the best catcher in the game right now with his preparation and what he puts into each and every game. You know as a pitcher that he’s going to be just as prepared as you are.”

“Everyone knows what kind of leader he is,” said Red Sox closer Jonathan Papelbon. “But the biggest thing for me is he leads by example. He’s able to do a multitude of things and [he] carries the load. It’s not one thing. For me, he does it all. He helps me with my confidence and the way he calls a game.”

Varitek is respected throughout the baseball world as one of the best to play the position. More important, the Red Sox players want him on that plate.

An older Red Sox generation may have called Carl Yastrzemski “The Captain,” but what if Jason Varitek wasn’t around today for the Boston Red Sox?

“It would hurt us big time,” Ortiz said.

jmcdonal@projo.com