Dan Koppen (AP)

FOXBORO — You want an assessment of the Patriots’ offensive line? Go to the most important cog in the machine, center Dan Koppen.

While Matt Light has him beat when it comes to seniority — by roughly two seasons — no lineman is more respected by his peers than the Boston College product. A fixture in the middle since he took over for an injured Damien Woody at center early in his rookie season back of 2003, Koppen has been every bit as durable as any other center in the league: Since the start of the 2003 season, the Patriots have played 128 regular-season games, and Koppen has started 119 of them.

With Koppen as the fulcrum of the o-line, the New England offense has finished in the top 10 in total offense seven times in his eight NFL seasons. The 6-foot-2, 296-pounder earned his first career Pro Bowl selection in 2007 and was named to the AP All-Pro Second Team, becoming the third center in Patriots history to earn all-star honors. And in 2008, Koppen started every game at center as part of an offensive line that supported the best rushing season for the Patriots in more than 20 years in terms of rushing yards, rushing touchdowns and average yards per carry.

The current group was honored on Tuesday with the presentation of the Madden Protectors Award, an award that “recognizes the accomplishments of the highest performing offensive line unit and their best-in-class ability to provide consistent, powerful protection,” according to the press release. The Patriots were selected based on a combination of analysis by John Madden and fan voting.

Since 2003, Koppen has been able to count on seeing many of them same guys to his left. On that side, it’s been  Light (left tackle) and Logan Mankins (left guard) on fairly constant basis since 2005, save for Mankins’ holdout last season over his contract situation. Both recently signed new deals.

“It’s great to have those guys back,” Koppen said. “The type of player Logan and Matt are, what they’ve done for this team they’re such good guys, and to have them in the locker room and have them as good friends. It’s really good to see them come back.”

Comparatively, the right side is fairly young: Sebastian Vollmer (right tackle) settled into his spot as a full-time starter at the beginning of the 2010 season. Meanwhile, Dan Connolly (right guard) has flip-flopped over the course of his brief career, moving from one guard spot to another when Mankins was out last season and also providing backup for former starting right guard Stephen Neal, who retired at the end of last season.

“Those are guys that really have progressed,” Koppen said. “Connolly is one of those guys who have come in our system and has really made strides. He’s got a lot of playing time last year and played well for us. And Sea Bass is just one of those guys where he just comes out and works every day. With his size and ability, he’s tough to beat.”

As for Koppen, he’s entering his ninth season in the NFL, and has learned a few things about getting through training camp.

“Camp is camp — [it’s all about] coming out here and starting over and trying to get better and get comfortable with the guys around and come together as a group,” he said. “Put your head down and go. Just do what the coaches ask and do it as hard as you can. if you mess up, learn from it and come back and do it better the next play.”

Koppen says the new practice schedule — less hitting, no two-a-days — is a “double-edged sword” for players.

“You might have less two-a-days,” he said, “but that one practice you’re out here for, it’s a doozy, so you have to have your mind right and be ready to go the whole way through. It’s a long practice, so you have to be mentally ready, mentally into it.”