"Honestly, I didn't realize we hadn't revealed it," Carroll said. "I don't even remember what game it was. It was somewhere in the middle -- I don't know. He was fine about it. He didn't miss anything. The same with [quarterback] Russell [Wilson]. He was fine about it. I don't know how they do that, but they did."
Sherman will not need surgery in the offseason. Carroll was asked why the Seahawks never listed him on the injury report with the knee injury.
"I don't know," he said. "I'm feeling like I screwed that up with not telling you that because that happened, but he was OK. So I don't know. He never missed anything, which is probably why."
Meanwhile, starting cornerback DeShawn Shead suffered a "significant" left knee injury that involves more than just an ACL tear.
"There's some other stuff, some other things that did go on, but I can't tell you the specifics of it," Carroll said. "It was a significant ACL injury with some of the other things that normally happen.
"It's going to be all the way until next season before he really gets to start seeing how far along he is and if he can come back."
Shead suffered the injury in the third quarter of Saturday's playoff game against the Atlanta Falcons.