Receiver Adam Thielen underwent season-ending ankle surgery this week, leading to him being placed on injured reserve Wednesday.
Thielen tried playing through a high ankle sprain suffered Dec. 5 when Lions cornerback Jerry Jacobs landed on his left foot. He returned three weeks later against the Rams, aggravating the injury in the second quarter when he was tackled low.
"Hope he had a good [surgery], Cook said, "get everything intact and get it right. Since I got here, he's been a true brother; true meaning of brother, not even football-related. Just being there for me. So I'm going to do the same for him, whatever he need.