Mathews has been playing with a sore ankle for the last three weeks, which limited his playing time in San Diego's 27-10 AFC wild-card win at Cincinnati last week.
San Diego coach Mike McCoy would not say if his star running back will be available for the team's rematch at Denver in the AFC divisional round on Sunday.
However, he did indicate that Mathews is on the same management plan that the training staff implemented the past two weeks, which is not practicing on Wednesday and Thursday, working as a limited participant on Friday and playing on Sunday.
Asked if the severity of his injury had changed, Mathews echoed McCoy, saying he's taking it day by day and trying to stay mentally prepared to play on Sunday.
"You're not going to be 100 percent," Mathews said. "There's a difference to playing hurt or injured. You've just got to keep going."
Mathews finished the regular season with a career-high 1,255 rushing yards, playing a full 16-game season for the first time in his four-year NFL career.
In San Diego's surprising 27-20 win at Denver last month, Mathews rushed for 127 yards on 29 carries, including a 23-yard run for a score. The Chargers are 7-1 this season when Mathews carries the ball at least 19 times this season.
Perhaps a greater concern for McCoy is the injury status of center Nick Hardwick, who did not practice on Wednesday because of a reaggravated neck stinger and a concussion.
"The whole game he was being diagnosed for his stinger," McCoy said about Hardwick. "And then after the game he had some concussion-like symptoms. So after the game, they diagnosed him with a concussion."
Hardwick is the only player on the offensive line that has not missed a game this season. The Chargers have used six different starting offensive line combinations, including five different players at left tackle.
However, the Chargers have used the same starting five up front for the past five games.
McCoy said Hardwick is going through the NFL's concussion protocol this week and has not been cleared.