Cooper took a big hit from safety Darian Stewart during the 21-14 win and was later ruled out with a concussion. Stewart earned a 15-yard penalty on the play for unnecessary roughness.
It turns out he will not only need to clear the concussion protocol in order to play next week against the Giants, he will also need to prove he can play through the ankle injury.
The 23-year-old caught only one pass before the injuries, although it went for a nine-yard touchdown. It was his fifth score of the year and second in as many weeks since the Week 10 bye.
It has been an up-and-down year for Cooper, who is coming off Pro Bowl appearances in each of his first two seasons. He has 42 catches for 499 yards, although the majority of his production came in Week 7 when he tallied 11 receptions for 210 yards and two touchdowns.
This was the only time he broke 70 yards all season and also has fewer than 10 receiving yards in four different games.
Despite his struggles, the Raiders could be in serious trouble if he is forced to miss more time. The league is apparently reviewing a possible suspension for receiver Michael Crabtree after his ejection Sunday, per Ian Rapoport of NFL Network.
If these players are out once again in Week 13, Oakland will have to rely upon Cordarrelle Patterson, Johnny Holton and Seth Roberts.