In recent weeks, San Diego Chargers running back Ryan Mathews has followed a routine of resting his injured ankle early in the week of practice, then giving it a go Friday before a Sunday game.

That routine has taken a little detour this week. Mathews did not practice Friday, even though head coach Mike McCoy believed that Mathews would be available to do so earlier in the week. Mathews is officially listed as questionable on the team's injury report.

This leaves Mathews' status very much up in the air for Sunday's divisional-round matchup with the Denver Broncos, and it's a huge concern if he can't go. Mathews was a pivotal figure in the Chargers' upset Thursday night victory in Week 15 in Denver, rushing for 127 yards and a game-changing 23-yard touchdown. The Chargers dominated the time of possession in that game and could struggle to do so again if Mathews if not ready Sunday.

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