MIAMI (AP) -- The NFL's concussion protocol wasn't strictly followed when Miami Dolphins quarterback Matt Moore was treated for a hit to the chin and mouth in a first-round playoff game, the league said Wednesday.

Because Moore was bleeding from the mouth, he was allowed to return to the game too quickly at Pittsburgh, the league said in a statement. The determination was made after the NFL and the NFL Players Association reviewed the case.

No disciplinary action against the Dolphins will be taken, but their staff must undergo a full review of the protocol, and future deviation may lead to fines against the team, the NFL said. There is no indication competitive issues had an impact on the care Moore received, nor did he demonstrate any concussion symptoms during or following the game, the league said.

Moore was hit in the second quarter as he threw a pass, and the play drew a roughing-the-passer penalty on Pittsburgh's Bud Dupree. Dolphins medical staff attended to Moore on the field, and he was evaluated on the sideline by an independent neurological consultant and team physician before returning to the game.

Moore missed only one play in Miami's 30-12 loss . He returned to the game four minutes after the hit, and two minutes after he went to the sideline. Following the game, Moore said he felt fine when he returned to the field.

The NFL determined the Dolphins' doctor took appropriate steps to promptly and fully involve an unaffiliated neuro-trauma consultant in the evaluation of Moore, and they jointly cleared him to return to the game. But they failed to recognize Moore presented a documented symptom -- bleeding from the mouth -- that required further evaluation in the locker room under the protocol, the league said.

The Dolphins were notified of the findings in a letter co-signed by Dr. Hunt Batjer, co-chair of the NFL Head, Neck & Spine Committee, and Dr. Thom Mayer, medical director for the NFLPA. The team declined an immediate comment on the findings.

"It is important for us to ensure everyone understands and follows the protocol, and that we continue to reinforce its importance," the league said. "The co-chairmen of the NFL's Head, Neck and Spine Committee sent a memo to the medical staffs of the clubs participating in the playoffs reminding them of that point."