When players break NFL rules designed to promote player safety, they pay fines and face potential suspension. What happens when teams violate, or outright ignore, player safety guidelines? The league will provide an answer soon. The NFL can prove its seriousness in protecting player welfare by holding teams to the same standard as players. Or it can expose the league’s concussion protocol as a toothless suggestion, merely a public relations shield.

Sunday afternoon, in the waning minutes of the St. Louis Rams’ 16-13 loss to the Baltimore Ravens, Baltimore defensive tackle Timmy Jernigan sacked St. Louis quarterback Case Keenum and slammed the back of Keenum’s head against the cold M&T Bank Stadium turf. Keenum wobbled as he attempted to roll onto his hands and knees, and he rose to his feet only with a teammate’s assistance. As the Rams attempted a game-winning drive, Keenum never left the field, despite obvious signs he could have suffered a concussion.

In that moment, Keenum morphed from a nondescript career backup to a crucial test case for the league. The NFL began a review “promptly after the conclusion of yesterday’s game” to determine why Keenum “was not removed from the game for the necessary evaluation by a team physician or the unaffiliated neuro-trauma consultant as required by our concussion protocols,” spokesman Brian McCarthy said in an e-mailed statement. The NFL Players Association launched its own investigation alongside the league.

The joint review comes at a critical time for the league’s concussion policies because of how the protocol has evolved. Prior to 2011, the league had no standard reaction to potential concussions. The NFLPA drafted a protocol, and eventually the league put one into place before the 2013 season.

Each year, failures and loopholes have been patched over. Last year, for example, two players complained of “stingers” when they actually suffered concussions and were allowed to continue playing. In the Super Bowl, New England Patriots wide receiver Julian Edelman appeared to suffer a concussion, but play never stopped, and so he stayed in the game.

In the offseason, the NFL and NFLPA adopted improvements. If a player reports neck pain along the lines of a stinger or “burner,” team physicians are required to test him for a concussion. To prevent another Edelman situation, the NFL gave an independent certified athletic trainer – known as an ATC spotter – the right to call time out from high above the field and have the player in question removed if he “displays obvious signs of disorientation or is clearly unstable” and “it becomes apparent that the player will remain in the game and not be attended to by the club’s medical or athletic training staff.”

At some point, the only modification left to make will be an enforcement mechanism. That point is now. In order for teams to stop sending potentially concussed players back to the field, the NFL will need to adopt formal punishments and start penalizing teams or independent medical personnel that put players at risk.

“The NFL does a great job of taking credit for things required by the Players Association,” said Chris Nowinski, the executive director of the Concussion Legacy Foundation. “They’ve been dragged kicking and screaming. This is a clear next thing they need to do: fine the teams. This is a young man with a brain injury being put in harm’s way for no other reason than the teams have no consequences for rolling the dice with his life.”

By the end of the week, perhaps, the league and the union will determine whether the Rams or the ATC spotter were in the wrong. The investigation should yield a definitive conclusion. All contact between the ATC and the sideline are monitored for review, and video is kept to determine what replays physicians did or didn’t watch. If the proper chain was not followed, the league and NFLPA will know. If it was and got ignored by coaches, the league and NFLPA will know.

Players across the league, one person close to the situation said, are watching the case with interest, waiting to see if the NFL will take any disciplinary action. McCarthy, the league spokesman, was cryptic as to possible punishment for the Rams or their medical personnel. Asked what recourse teams faced for violating the protocol, McCarthy replied, “Our focus right now is on ensuring that the protocols are followed.”

The notion of a league fining teams for a breach in safety protocol is not only reasonable in theory. It exists in practice:  Australia’s National Rugby League fines teams $20,000 for violating its concussion protocol.

First, the league will need to determine if the Rams or their doctors violated protocol. Nowinski already has made up his mind.

“Everybody saw the injury,” Nowinski said. “You have to imagine nobody pulled the trigger because it was the last drive of the game. That was a very unethical thing to do: to put that player at risk for a catastrophic injury.”

Monday evening, Rams Coach Jeff Fisher, a member of the competition committee that signed off on the concussion protocol, offered his explanation of the “combination of unusual events” that led to Keenum being placed in that position.

From the sideline, Fisher saw Jernigan slam down Keenum. But with under one minute remaining, the clock ticking and myriad decisions to be made, Fisher said he was in “game-management mode” and never saw the aftermath.

“I didn’t see him struggle to get up,” Fisher said. “I didn’t see anything from my vantage point on the sideline of Case’s slow recovery. The shots you’ve seen of him struggling to get up, I didn’t see that.”

Rams head athletic trainer Reggie Scott saw Keenum struggle. Scott bolted on to the field as the officials marked off a penalty on the play against the Ravens. “He questioned Case,” Fisher said. “Case said he felt okay.”

Because Scott entered the field to talk with Keenum, Fisher said, the ATC spotter believed it was unnecessary to alert officials and halt the game. The officials spotting the ball never saw Keenum wobble. As they readied to start the play clock, Fisher said, they told Scott he needed to leave the field or there would be a costly 10-second runoff.

“The head trainer was told to leave the field,” Fisher said. “Keep in mind, we’re in a critical point in this game.”

The ATC spotter eventually notified officials that Keenum had shown signs of brain trauma, Fisher said, but only after the Rams lost the ball and Keenum was out of the game, anyway. Because of the speed at which the events unfolded, Fisher believed no one was at fault. “You cannot, in these circumstances, place blame on anybody,” he said.

There is a difference, though, between blame and responsibility. If the league finds a violation, it should punish the Rams, and not just to make an example out of them. An NFL sideline is pure chaos, especially in the throes of a game-deciding drive. Perhaps Fisher really left Keenum in because he didn’t notice his quarterback wobbling, the specifics and stresses of the game commanding his entire focus. Fine. Game-management mode needs to include knowing that your quarterback just got his brain scrambled. You can even feel sympathy toward Fisher and believe that.

The NFL still needs to send the message that the stage or complexity of the game cannot be an excuse. The health of its players always should be the priority, whether it’s the first quarter or a two-minute drill. Football is inherently violent and dangerous to its players. Desperation doesn’t change that. The NFL doesn’t care about a player’s intention when it delivers a helmet-to-helmet blow. The action is what draws a fine.

Sadly, what happened two plays after Keenum’s head met the turf might force change among coaches. Keenum dropped back to pass. He barely reacted as defensive end Courtney Upshaw rushed him and swatted the ball from his grasp. The Ravens recovered, and after a short drive they kicked a game-winning field goal.

“I hope somebody learned a lesson when he fumbled the ball,” Nowinski said. “Having concussed players on the field is a bad idea from a competitive perspective.”

The NFL can’t let that be the only deterrent. It needs to punish teams who behave recklessly with their players’ health, wittingly or not. If it does not, we will know where the league’s priorities truly lie.