Chris Clemons has sustained a knee injury which is likely to keep him out of the Seattle Seahawks' playoff game against the Atlanta Falcons this weekend.

The Seahawks believe that the defensive end may have sustained an anterior cruciate ligament tear in the win over the Washington Redskins yesterday.

The 31-year-old's agent has described the knee as feeling loose but not painful, and is blaming the condition of the turf at the Redskins' FedEx Field for the injury.

If the tear is confirmed, Clemons will likely need surgery in the near future, and would face a battle to be ready for the start of the 2013 season.

Clemons has been the Seahawks' top pass-rusher this season, and has 11.5 sacks and three forced fumbles.