Dwayne Washington a no-go for Lions' matchup with Rams

The Detroit Lions will be without their top two running backs Sunday against the Los Angeles Rams as Dwayne Washington will not play due to an ankle injury, a source told ESPN NFL Insider Adam Schefter.

The Lions already had ruled out starterTheo Riddick (ankle injury) this past week.

That means second-year pro Zach Zenner and recently signed veteran Justin Forsett will split carries Sunday, the source told Schefter.

Washington suffered the injury againstChicagoin Week 4. He did not play in Week 5 and sat out practices Wednesday and Thursday this past week. He returned to practice on a limited basis Friday, but had looked good running and cutting off on the side earlier in the week.

He had been listed as questionable on Friday's injury report.

Detroit is already without its No. 1 running back to start the year, Ameer Abdullah, who is on injured reserve after foot surgery.

Forsett signed with the Lions on Tuesday after being released from Baltimore earlier in October. He had 31 carries for 98 yards this season for theRavens. Zenner has 10 carries for 21 yards and three receptions for 45 yards this season.

Detroit could use more of receiver Golden Tate in the backfield for the second straight week. He had three carries for six yards against theEagleslast Sunday.