Fantasy owners waiting for Ryan Mathews to return from his knee injury will need to be a bit more patient, as U-T San Diego reports he is likely to miss at least one and possibly two more games, including Week 6 against the Raiders.
The emergence of Branden Oliver might lessen the pain of Mathews' absence, but this team badly needs Mathews back. Donald Brown has flopped in his turn as the primary option, so there is little reason to think Mathews won't get the job back when he returns. Though Oliver looked good in Week 5, he has a limited track record of success and should not be much of a road block to Mathews getting his job back.
The Chargers like to use multiple running backs in their offense, and Oliver could fit into the Danny Woodhead role. Even playing alongside Woodhead, Mathews still managed 90 all-purpose yards and seven touchdowns a year ago, so don't worry about his role. Just get healthy, Ryan.