Running back Ryan Mathews was a full participant in training on Tuesday and said he was "optimistic" about playing on Sunday against visiting Buffalo. Mathews has missed the last three games after suffering a concussion in the 20-19 loss to Miami.

"I felt good. I was happy to be back out there with my teammates. My legs were a little rusty, but I was happy," Mathews said. "I'm feeling good, I'm feeling good. I just have to take it day by day and just do what I can. I'm really optimistic about it and whatever the coaches and the training staff have planned for me, that's it."

Mathews has 427 rushing yards on 75 carries this season and is averaging a lusty 5.7 yards per carry with five touchdowns. He's also caught 14 passes for 119 yards and a touchdown.

"I want to get back out there and inspire all of my teammates," Mathews said. "It's all about having fun. I've got to take it slow. I haven't played and ran and done stuff in a few weeks. I've got to break it in."

Mathews said he was patient with the team's athletic training staff during his recovery, which turned out to be longer than many concussions. Now that he is cleared to take part in training, Mathews wants to make sure the rest of his body is ready to go for Buffalo.

"It's amazing how the speed can change and how fast it is," Mathews said. "You take a few days off, a week off, a couple of weeks off and come back and it's fast. You've got to get the timing down and really just get your legs back under you."