Ryan Mathews' Fantasy Value Won't Recover Due to Branden Oliver's Presence

San Diego Chargers running back Ryan Mathews was a popular fantasy option entering the 2014 season, but an injury quickly derailed his campaign. Even when he returns, though, his ceiling will be significantly lower than originally thought.

Durability issues largely prevented Mathews from reaching his potential during his first three NFL seasons. The Fresno State product was able to dress for all 16 games in 2013, however, and it resulted in a career-best season of over 1,200 rushing yards and seven total touchdowns.

Even after such a fine showing, there was apparently still concern among Chargers management about Mathews' ability to stay healthy. With third-down back Danny Woodhead already on the team, the Bolts signed Donald Brown as insurance during the offseason.

Interestingly enough, all three of those players have found themselves on the injury list this season. Mathews is out with an MCL sprain, Woodhead is done for the season with a broken leg, and Brown is nursing a concussion.

That paved the way for undrafted rookie Branden Oliver to become the starter, and he has made the most of it thus far. Having received the bulk of the touches over the past two games, the University at Buffalo alum has racked up over 300 total yards and three touchdowns.

Despite being just 5'7" and 208 pounds, Oliver is an extremely tough runner. That is why the description from Sports Illustrated's Greg A. Bedard is an apt one:

Mathews has missed the Bolts' past four games, and he is going to miss their Week 7 clash with the Kansas City Chiefs as well, according to the team's official Twitter account:

Per NFL on ESPN, Mathews was originally slated to miss four or five contests:

That timetable would put him in line to return next week against the rival Denver Broncos, but that is far from a sure thing. In fact, the 27-year-old back hasn't even been cleared to start running yet, according to Michael Gehlken of U-T San Diego.

As things currently stand, Mathews is unsure of when he will be able to get back out on the field, but he hopes it's soon.

"I'm hoping," Mathews said, according to Gehlken. "I'm just taking it one day at a time. When they think it's time for me to start running, then it's time to start running. It's all in their hands."

That uncertainty can't have Mathews' fantasy owners feeling too confident, especially since Oliver will become further entrenched with each start. San Diego's running attack has become more potent since the top three backs went down to injury, and that has to bode well for Oliver's chances of maintaining a huge role moving forward.

There is no question that Mathews will be utilized to some degree when he does return, but there isn't necessarily anything that he does better than Oliver. The rookie is a great pass-catcher with four receptions in each of his past three games, he has blazing speed, and he is a capable between-the-tackles runner despite his diminutive size.

The best-case scenario for Mathews owners at this point is for him to return and get a 50-50 split in terms of touches. Even that is a stretch, though, because of Oliver's form and due to the fact that Mathews will need some time to ease back in to the swing of things.

Most owners probably drafted Mathews as an RB2, but he'll struggle to post reliable flex production when he comes back. Oliver has gone from an unknown to the Chargers' top fantasy running back, and not even Mathews will be able to change that.

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