The contract of Red Sox catcher Jason Varitek will run out after this season. Boston’s captain is having his worst offensive season since becoming the team’s starting catcher almost a decade ago.

The Providence Journal / Gretchen Ertl

TORONTO –– There’s not much time –– just 10 days –– remaining in the regular season, and because of that, Jason Varitek knows that his Red Sox career could be winding down, too.

Varitek’s four-year, $40-million deal expires this fall, and he is uncertain where he will play next season. With Manny Ramirez dealt at the trading deadline and the core of the team under contractual control, Varitek stands to be the team’s highest-profile free agent this winter.

After some brief, broad discussions in spring training, Varitek’s agent, Scott Boras, and Red Sox management haven’t discussed a new deal. That shouldn’t be a surprise, since the Sox generally frown upon in-season negotiations for fear that they will act as a distraction.

Boras, meanwhile, almost always advises clients this close to free agency to explore the market and invite other teams to bid.

When Varitek was last eligible for free agency, it took several months before he agreed to a new deal to remain with the Red Sox despite the relative lack of other offers.

Most teams believed Varitek wouldn’t leave Boston and, feeling that their interest would serve to only escalate the catcher’s salary demands with the Red Sox, stayed out of the bidding altogether.

Perhaps this is why this time around, Varitek declines to make even the most general statement about his pending free agency. Asked recently whether, all things being (monetarily) equal, he would prefer to end his career with the Red Sox, Varitek demurred.

“I can’t say that,” he said, shaking his head slowly. “I don’t know. I really don’t.”

Varitek’s foray into free agency doesn’t come at a good time for the 36-year-old catcher, who is muddling through his worst offensive season since becoming the team’s No. 1 catcher almost a decade ago.

As the Sox begin their final road series of the season tonight here, Varitek is ranked near the bottom of American League catchers in most significant offensive categories. Among A.L. catchers with a minimum of 300 plate appearances, he’s 11th in OPS (.676); 11th in batting average (.223) and 10th in RBI (39). His 116 strikeouts, meanwhile, rank him second.

Of course, a catcher’s value and Varitek’s specifically can’t be measured solely by batting average and other traditional measuring methods. His catcher’s earned run average –– the team’s ERA while he is behind the plate –– is 3.69, best among A.L. receivers, and while he’s nabbed just 23 percent of potential base stealers, he’s committed just four errors behind the plate.

And there’s Varitek’s contributions as a leader –– both of the pitching staff, and the team as the club’s captain.

Still, Varitek’s offensive downturn is bound to work against him at the negotiating table. He’s on pace to finish with his lowest RBI since 2001, when an injury limited him to just 51 games and barring a strong finish, will end the season about 40 points off his lifetime batting average of .267.

Those numbers will serve to only reinforce the notion that catchers are subject to a dramatic drop off as they reach their mid-30s.

As Varitek combed through a thick binder of advance scouting reports recently, he took time to address his future, however uncertain.

“It’s there,” acknowledged Varitek of his pending free agency, “but I have other things on my mind to distract me. It’s real; it’s a real thing. But I’m trying to focus on finishing the season and helping us win as many games as possible.”

Asked whether he believes the Sox will take a harder line on a new deal because of his offensive struggles, Varitek is noncommittal: “I can’t answer what they’re thinking.”

But just as quickly, Varitek strives to point out that his offensive struggles were limited to “a month...a month and a half,” and that his offensive game “is still there.”

(After a strong May, in which he hit .299, Varitek tanked in June and July, hitting a combined .157 with two homers in 42 games. He rebounded last month to hit .264, though he’s hit just .200 this month so far).

Moreover, he maintained that he still has the strength and durability to be a No. 1 catcher.

“I still have what I need,” he said. “The strength, the ability. I’ve been able to play day games after night games and handle the load.”

Another four-year deal would seem out of the question, though Jorge Posada signed a four-year deal with the Yankees last offseason at about the same age Varitek will be this winter.

Then again, Posada was coming off a season in which he hit a career high of .338. Moreover, the Yankees themselves might be rethinking the wisdom of their four-year, $52-million deal after Posada underwent season-ending shoulder surgery this summer on his throwing arm, putting his future behind the plate in doubt.

“I want to play as long as I can,” Varitek said succinctly.

One thing Varitek won’t do is blame his struggles on a trying personal year. Varitek filed for divorce from his wife this summer, but when asked whether he has been distracted by off-field issues, Varitek is adamant.

“I’m not even going there,” he said firmly. “It is what it is, and I don’t want to get into excuses.”

Instead, he blames some of his problems on some tinkering he initiated with his mechanics at the plate. While declining to identify the specific changes to his swing, he says ruefully: “I know I created a lot of my own struggles. No excuses –– I just did. I started to make some changes and got into a hole –– that’s reality. I did that to myself. I can be my own worst enemy at times.”

If the Sox’ interest in him has cooled, it’s not as though they have any other viable options from within. Kevin Cash is a serviceable backup, but is not the full-time answer.

George Kottaras, scouts agree, needs work defensively and couldn’t be expected to take over in 2009. Mark Wagner, perhaps the team’s best long-term option, needs more development time.

As for what the future holds for him, Varitek is unsure: “That will be answered, in part, by what (the Red Sox) want to do. Time will answer that.”

And as the regular season winds down, Varitek can’t help but be mindful that when it comes to playing in Boston, time could be running out.

smcadam@projo.com