"It's as simple as that," McCoy said.
Mathews wore a walking boot to protect his ankle Wednesday. He has played in all 15 games despite leaving one game with a concussion and two others with a hamstring injury.
"There's a big difference between being injured and being hurt," Mathews said. "I'm just trying to work hard and be there for my teammates, and that's all that matters, being there for my teammates."
For Mathews, drafted 12th overall in 2010, it would be his first season without missing a game. He has rushed for a career-high 1,111 yards in helping the Chargers (8-7) stay in playoff contention.
"I try to be as good as I can be for the linemen up front," he said. "They block their tails off."
Mathews was hurt during a 26-13 victory over the Oakland Raiders on Sunday. He ran for 99 yards and a touchdown. He left in the second half but briefly returned to the game.
"He's doing fine," McCoy said. "He'll be ready. He's got a great frame of mind right now. I'm looking forward to him having another big game."
The Chargers remain a long-shot to earn the AFC's No. 2 wild-card berth. They need to beat the Chiefs and have Miami and Baltimore both lose or both tie. San Diego also can get in if it ties Kansas City and the Dolphins and Ravens both lose.
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