Ryan Mathews, who's having a career year, had a bandage on his left ankle after Sunday's 26-13 victory against Oakland that helped keep alive San Diego's long-shot playoff hopes. Mathews left the stadium wearing a protective boot.
"I'll give you an update as the week goes along," McCoy said when asked how serious Mathews' injury is.
Asked specifically what the injury is, McCoy said: "Like I said before, I'll give you an update as the week goes along."
Mathews ran for 99 yards and a touchdown Sunday, pushing his season total to a career-best 1,111 yards. He limped to the locker room in the fourth quarter but later had a brief return to the field.
Mathews fell 1 yard short of his third straight 100-yard game and sixth overall this season. While he was once known for fumbling and being somewhat fragile, Mathews has been strong this season. Earlier this month, he carried a combined 58 times for 230 yards in victories against the New York Giants and Denver Broncos in a five-day span.
McCoy did say he expects everyone to be healthy Sunday, except for tight end John Phillips, who was placed on injured reserve Monday with a knee injury.
Does that include Mathews?
"Like I told you, I'll give you an update as the week goes along. But I expect him to play," the coach said.
McCoy claimed that he didn't know all the details of Phillips' knee injury.
San Diego (8-7) survived Sunday because Miami and Baltimore both lost. In order to clinch the AFC's second wild-card spot, the Chargers must beat Kansas City and have Baltimore and Miami both lose or both tie. San Diego could also get in with a tie plus losses by Miami and Baltimore.
The Chargers are trying to end a three-year playoff drought.
"We have a lot of work ahead of us before that time and we have to beat the Kansas City Chiefs," McCoy said. "If we don't beat them, we're not in. That's our No. 1 concern right now. Win this game this weekend."
The Chargers hardly played a perfect game Sunday. They overcame three first-half turnovers and had to settle for field goals four times, including three times after getting inside the Raiders' 20-yard line.
"We are just trying to score one more point than the other team," McCoy said. "There are always things we can improve on. As long as we score one more than the opponent a win is a win. There is no such thing as a bad win in this business."
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