David Ortiz, Jon LesterBOSTON — One man has anchored the Red Sox’s lineup for more than a decade. The other has been a rotation stalwart since breaking into the majors in 2006. Now, the successful run as teammates enjoyed by David Ortiz and Jon Lester could be nearing the end of its course.

Lester is set to become a free agent after this season, and with the Red Sox thus far unable to work out a contract with their ace, there’s growing speculation that the pitcher could be dealt before Thursday’s Major League Baseball non-waiver trade deadline. Ortiz is a bit perplexed by such rumors, though confident the duo will share a clubhouse beyond 2014.

“It’s the time of the season where, as a GM, you go out there and change what you can change,” Ortiz said before Monday night’s game at Fenway Park. “The trade rumor about my left-hander, I don’t know where it comes from. It might come from the front office or whatever, but you talk about trading a player like that, that caliber of player in today’s day, you must be getting half the team of some places. This is a really good player.

“I still believe that at some point they’re going to get to an agreement and get to enjoy seeing Lester pitch another eight, 10 years, whatever. He’s a guy that you enjoy watching pitch, no question about it.”

Ortiz joined the Red Sox as a free agent before the 2003 season, and the nine-time All-Star has been one of the league’s most feared sluggers ever since. Before spring training this year, Ortiz landed him a contract extension that runs through at least the 2015 season — with options for 2016 and 2017.

Lester is a homegrown talent, having been drafted by the Red Sox in 2002. The Red Sox were unable to hammer out an extension with the lefty during spring training, though, and his future with the organization remains in doubt, especially with reports surfacing that Boston could look to trade him this week.

ESPN.com’s Jayson Stark reported that the Red Sox have contacted contenders and told them Lester could be available for the right package of prospects.

“Like I always say, I’m just another player here where I’ve got no choice but to agree with whatever,” Ortiz said Sunday at Tropicana Field, according to WEEI.com. “The front office is hard to do and they’ve been talking about trading Jon. That sounds like a rebuilding, that type of situation. I don’t know. There’s not much I can say about it, but they’ve probably got their reason to do it. Hopefully it doesn’t happen. Lester is one of the best pitchers in the game.”

Lester said Friday that he’d be open to re-signing with Boston over the offseason even if the Red Sox trade him before the deadline. The three-time All-Star added another interesting wrinkle Sunday, telling WEEI.com that it’s unlikely he’d sign an extension with his new team if traded, as his ultimate goal still is to sign with Boston. It’s unclear whether the Red Sox are willing to make a substantial enough offer to the 30-year-old, but there’s no denying his impressive track record.

“He’s young, very talented, won a couple World Series,” Ortiz said Monday. “He’s in his prime. What else?

“This market is tough,” Ortiz added. “You have a guy that through his career playing here has been able to do what he’s done, he’s a keeper. He’s a keeper. We’ll see. We’ll see what happens.”

Ortiz and Lester — both key contributors in the Red Sox achieving World Series glory — shared a clubhouse Monday. Going forward, any day, theoretically, could be their last together