NEW YORK -- The Green Bay Packers and Tampa Bay Buccaneers have been warned by the NFL that assistant coaches who comment publicly about retaliation against players will be severely disciplined by the league.

The warning came in a memo written by commissioner Paul Tagliabue following comments by Packers offensive line coach Larry Beightol after the hit Sunday on Green Bay tackle Chad Clifton by Tampa Bay defensive lineman Warren Sapp.

The memo was sent Tuesday evening, said a source within the league who requested anonymity.

The league has ruled the hit by Sapp on Clifton was legal. It came after an interception by Brian Kelly in the Bucs' 21-7 win over Green Bay.

Clifton remains hospitalized with a severe hip injury and could miss the rest of the season.

The memo resulted from a telephone call between Beightol and Buccaneers defensive coordinator Monte Kiffin on Monday in which Beightol suggested Sapp can expect to be cut blocked the next time the teams meet. The Bucs (9-2) have the NFL's best record and the Packers (8-3) are far ahead in the NFC North, meaning a playoff meeting is possible.

"I told Monte that we weren't going to cut him Sunday because we didn't want to ruin their season," Beightol told the Milwaukee Journal-Sentinel following the conversation with Kiffin. "If we play them again, he's fair game. Somewhere, we'll see him."

Tagliabue, in his memo to top executives of both teams, including coaches Mike Sherman of Green Bay and Jon Gruden of Tampa Bay, said the league would monitor future developments between the teams and will crack down on any inflammatory comments. Sherman confronted Sapp after Sunday's game about the hit, but said Monday he was sorry the controversy had taken away from the game itself.

"Please make certain," Tagliabue said in the memo, "from today and going forward that there is no further public criticism of the opposing team, players or coaches, or other public comments or threats of injury or retaliation related to these matters.

"Please also understand and advise your staffs that any such criticism or comment will constitute conduct detrimental to the league or professional football, and will be the subject of very substantial fines or other disciplinary action, including potential suspension of assistant coaches."