A lack of second-half work combined with playing from behind made for a slow day statistically for Ryan Mathews. Of his seven carries at Washington, only one came in the second half.
When Mathews posted back-to-back 100-yard performances in Weeks 6 and 7 they came in games where the Chargers needed to kill the clock in the second half. The second half of Week 6 had him get 11 carries for 55 yards; the second half of Week 7 had him get 12 carries for 56 yards and a score. When I ranked Mathews as a No. 2 Fantasy running back it was under the idea he'd have to kill the clock at Washington. It didn't work out that way -- the Chargers leaned on Danny Woodhead for much of the third and fourth quarters.
I'd call it unlikely the Chargers will need to kill the clock in Week 10 vs. Denver. I'd shy away from using Mathews then.