Patriots guard Logan Mankins tore his right ACL in Week 1 of last season, and tore his left MCL in the Divisional playoffs last season, reports ESPN NFL Insider Adam Schefter.

Mankins had left the Patriots' Week 16 game vs. Miami with a left knee injury, which was later reported to be a sprained MCL. He missed Week 17, but returned for the playoffs. Mankins underwent right knee surgery in February.

Schefter adds that Mankins may be the only player in NFL history to have played an entire season with a torn ACL. He started Super Bowl XLVI with torn ligaments in both knees.

Other than Sept. 28, when he did not practice with an illness, Mankins was not listed on the Patriots' injury report until Week 17, when he did not practice.

Mankins began training camp this season on the physically unable to perform list. When he returned to practice on Aug. 12, Mankins wouldn't reveal when he suffered the knee injury that required surgery, only saying "it happened a long time ago, a lot longer than you would have thought it happened."

"It wasn't 100 percent, but it was still functionable," he explained in August of the torn right ACL. "I could still run, so there was no reason to sit out. There were no MRIs or anything, so we never knew exactly what was hurt. If you can still run and play, there is no reason to go see a doctor, right?"

It wasn't until an MRI taken after Super Bowl XLVI that the exact injury was discovered.

"I knew something was wrong with it. I didn't know to what extent," he said. "It was a little surprising."

In August, Mankins joked that his approach to playing through the injury last season was to "put a brace on, tape aspirin to it, and go."