KANSAS CITY, Mo. (AP) — Kansas City Chiefs wide receiver Rashee Rice is “very optimistic” that his knee injury is not as serious as first feared and that his recovery time could be “much shorter” than initially believed, a source told Adam Schefter of ESPN on Monday with

It's still unlikely Rice will play again this season, but doctors won't know for sure until after surgery Tuesday morning, the source said.

Rice injured his right knee in the Chiefs' Week 4 win against the Los Angeles Chargers. It was initially reported that Rice suffered a torn ACL, but the team has yet to officially clarify the nature of the injury. The lateral collateral ligament (LCL) in his knee is damaged, a source told Schefter.

The Chiefs placed Rice on injured reserve on Thursday, sidelining him for at least the next four games.

Rice was injured when quarterback Patrick Mahomes accidentally collided with his knee as the two and other players were chasing a Chargers fumble that followed an interception.

Rice led the NFL in receptions with 24 in Week 4 and ranked second with 288 receiving yards.