Chargers OLB Dwight Freeney eager to prove himself going into 13th season

San Diego Chargers running back Ryan Mathews, right, runs a drill as he is tethered to teammate running back Danny Woodhead, left, during NFL football minicamp at the team's facility Tuesday, June 17, 2014, in San Diego. (AP Photo/Gregory Bull) (The Associated Press)

San Diego Chargers quarterback Philip Rivers claps during NFL football minicamp at the team's facility Tuesday, June 17, 2014, in San Diego. (AP Photo/Gregory Bull) (The Associated Press)

Now 34 and entering his 13th NFL season, Dwight Freeney is looking forward to proving himself all over again.

Freeney is rehabbing a quadriceps injury that shelved the outside linebacker after just four games last season, his first with the San Diego Chargers.

Although Freeney was mostly working on the side during the first day of mandatory minicamp Tuesday, he says he could play right now.

Freeney says he has no problem proving himself to everyone else, regardless if he got hurt, "because there's always going to be that question mark."

Freeney had 107 1/2 sacks in 11 seasons with Indianapolis before being allowed to leave after the 2012 season. He signed a two-year deal and had one-half sack last year before getting hurt.