FOXBOROUGH, Mass. – Logan Mankins has been a question mark for some time with the Patriots.

New England’s perennial Pro Bowl left guard underwent offseason surgery to repair a torn anterior cruciate ligament in his right knee, and no one with the Patriots — including Mankins — really knew how long the recovery process would take.

As such, Sunday’s opener at Tennessee has been in doubt for a good long while. Playing, not playing — who knew? But it appears Mankins has finally eased all fears.

“I never knew how fast I would heal and everything would progress,” he said. “But so far, it’s been good.”

New England has never needed him more.

With a handful of familiar faces missing from the offensive line, the Patriots are counting on Mankins to anchor a relatively youthful front five tasked with perhaps the most pivotal role in the league — protecting two-time MVP quarterback Tom Brady.

“It’s coming together,” Mankins said. “We’ve had a couple guys miss a lot of time, so we’re still working on it. We’ve got a lot of work to do.

“Hopefully we can put our best out on the field Sunday, play good together, we’ve got to trust in each other, and work together. We’re going against a good team. They’re a young defense, they’re very athletic, very fast and they play really hard. So, it’s going to be a big challenge.”

Piecing together the line was the first hurdle the Patriots had to overcome.

Mankins suffered the injury sometime before last year’s Super Bowl loss to the Giants. He said during this summer’s training camp that it “possibly” could have occurred during the regular season. However, the seven-year veteran still played against New York in Indianapolis before having surgery. He saw limited action this preseason, as well.

That was just the beginning of the transformation.

Three-time Pro Bowl left tackle Matt Light retired, longtime center Dan Koppen was cut a week ago and Brian Waters, the six-time Pro Bowl standout at right guard, has yet to report to the team. That leaves a projected offensive line that will average nearly 28 years of age, with Mankins and Dan Connelly the elder statesmen at 30.

“I am getting old, 30. See all this gray hair,” Mankins asked, showing no signs of graying. “I guess it happens to us all.”

Nate Solder, in his second year, is charged with protecting Brady’s blind side, something Light did for nearly 11 years.

“My technique has come around a little bit,” Solder said, “understanding the schemes better, understanding the system better, it’s all kind of helped.”

With Mankins to his left, Ryan Wendell, 26, will likely be at center. Wendell has played a reserve role during his three seasons in New England, but Coach Bill Belichick doesn’t seem concerned with the undrafted free agent from Fresno State.

“When we first had Wendy, we released him off the practice squad and then brought him back to the practice squad, so that’s a guy whose level has risen dramatically,” Belichick said. “He’s gotten better with technique, he’s gotten stronger.

“He’s just become a better football player. A lot of hard work, a lot of stringing good days together.”

Connelly should start at right tackle and Sebastian Vollmer, now in his fourth season, at right guard.

Mankins discussed the need for strong communication on the left side of the line, while still trusting everyone to do their jobs. It’s sure to be loud at Tennessee, and with chemistry an issue, hearing can’t be.

“It’s when we start worrying about what the guy next to you is doing,” he said, “is when things get messed up.”