The Kansas City Chiefs lost Jamaal Charles in the first quarter of Sunday's game against the Denver Broncos after he suffered a high ankle sprain, while the San Diego Chargers lost Ryan Mathews to a sprained MCL in the fourth quarter against the Seattle Seahawks. Who will fill in for them this week?

Despite the expected extended absences for these feature backs, the Chiefs and Chargers might be just fine with their backups. In Kansas City, second year running back Knile Davis took over after Charles suffered his injury, rushing for 79 yards and two touchdowns and added six receptions for 26 yards. Quarterback Alex Smith was impressed with his performance and head coach Andy Reid looks like he'll stick with him on Sunday against the Dolphins.

"I don't think it will change much from what you saw (Sunday)," Reid said of Davis' role, in this ESPN Kansas City Chiefs blog. "He was involved in a lot of different areas. I'm not saying number of carries or anything, but you saw him going in and playing a few different ways."

Davis showed his worth after recording only six total yards on two touches in Week 1 against the Tennessee Titans, and if Charles misses an extended period of time he'll likely continue to carry the load, which is big news for fantasy owners. Charles was a top three pick in fantasy drafts this year and many are going to need to find a way to replace him.

As for San Diego, Ryan Mathews is expected to miss 4-5 weeks after being carted off the field on Sunday with an MCL sprain, which opens the door for former Indianapolis Colts' running back Donald Brown. Chargers head coach Mike McCoy noted his confidence in Brown because of his experience and knowledge at the running back position and in the team's offensive scheme. Brown saw action on Sunday against Seattle, but wasn't very impressive.

He carried the ball seven times for just 21 yards and caught three passes for 10 yards, but in his defense the Chargers running game was weak as a whole on Sunday (37 carries for 101 yards) and he was stopped for a loss on one of Rivers' passes. Nonetheless, the Union-Tribune San Diego expects Brown to "absorb the bulk" of Ryan Mathews' work in his absence while running back Danny Woodhead assumes his current role in the offense.

The Chargers will visit the Buffalo Bills on Sunday, who have allowed just 166 rush yards in their first two games against the Bears and Dolphins.