Arden Key, one of the Raiders' better reserve players, is expected to miss the remainder of the regular season after sustaining a broken foot in last week's win over the Lions, according to NFL Network's Ian Rapoport. Key, per Rapoport, is getting a second opinion on the injury. 

Key has spent the season playing behind first round pick Clelin Ferrell and has recorded sacks in each of Oakland's last two games. He seemed to be finding his way after a rocky rookie campaign that saw him record just one sack in 10 starts. The former LSU standout underwent a rigorous offseason training regiment heading into the 2019 season. He also spent more time talking to veteran players on both sides of the ball about what he could do -- from both a mental as well as from a technical standpoint -- to become a better player. 

"I got a little stronger, which helps with the bull rush, and now that's my [baseline] move," Key said during training camp when asked about his offseason improvements. "So much of the credit goes to Buck (defensive line coach Brentson Buckner). I'm really starting to use my hands now. Last year, I didn't use hands at all. I was using my shoulder and a lot of forearm. If I can use my hands to keep guys off me, I can make moves and use my bend and length and things of that sort."

Key's injury is certainly a setback for the Raiders, who are off to a surprising 4-4 start after winning just four games during the 2018 season, Jon Gruden's first season back as a head coach after a decade absence. Key's recent surge was definitely a welcomed sight for an Oakland team that has just 15 sacks entering Thursday night's game against the Chargers. 

With Key out, expect more snaps for defensive end Benson Mayowa, who leads the Raiders with 5.5 sacks through eight games.