The New England Patriots have utilized substituting eligible and ineligible players to confuse opponents in the past two playoff games.
Carroll said he was told referees will make new signals to properly identify who is and isn't eligible on a given play.
"We made a call and asked about that. They came back with a very clear response," Carroll said. "They're going to have a new signal that designates when a player is, with an ineligible number, will be eligible -- that's the same -- but when an eligible number is now ineligible, they're going to make new a declaration to the players on the field, so that you'll clearly identify that. I know the league is absolutely committed to getting that right and doing that well. The Patriots have brought that to the forefront, because they've been using some stuff like that lately."
Carroll said referees will point to an eligible player and will make an arm-crossing motion at the knees for a player reporting as ineligible -- several reporters present have said the motion Carroll portrayed looked like The Charleston.
The Seahawks coach claimed officials made a mistake during the AFC Championship Game on a Patriots touchdown throw to Nate Solder, when they allowed a player who had reported eligible the previous play to remain in the game as an ineligible player without indicating, causing confusion for the defense.
"We've been preparing for it every day, because we don't want to be caught in a mishandling on our end," Carroll said. "So it's really on us to see it -- the officials do what they do -- but we still have to find it, because it could happen like it did to the Colts. So we're very much in tune with it. It's just been a part of the preparation, so it's not a big deal to us now."
UPDATE: NFL VP of officiating Dean Blandino clarified Carroll later Thursday, telling reporters that officials pointed out ineligible players during the AFC Championship Game:
"I think it was just in the conversation, he may have misinterpreted that it was new," he said. "We actually did do it during the AFC Championship Game."
Blandino also said that the Solder TD was in fact an illegal play and should have been penalized.