The Raiders left London with a big 24-21 Week 5 win over the Bears, but lost one of their young defensive players while doing so. 

NFL Media's Ian Rapoport reported Tuesday that Raiders defensive end Arden Key strained his patellar tendon Sunday and is expected to miss a couple of weeks. The team is expected to work out players at his position this week during their bye. 

Key, a third-round draft pick last year, has had a slow start to the season. He has played in all five games for the 3-2 Raiders, but only has one assisted tackle and two quarterback hits.

Coach Jon Gruden called for more production from the second-year pro a few weeks ago. 

“We have got to get more out of Arden. I’ve said that for long enough,” Gruden said after the Raiders' Week 2 loss to the Chiefs. “Arden, if you are listening, we got to get you going."

[RELATED: Raiders rookies shine bright in wild London win over Bears]


If Key is to step it up this season for the Silver and Black, it won't be for quite some time.