The National Football League and its players' union are scheduled to hold a mandatory conference call Tuesday with athletic trainers. This comes after St. Louis Rams quarterback Case Keenum remained in a game Sunday after suffering a concussion.
The injury happened at a critical moment with just over a minute left in a tied game. The Rams were focused intently on a late score -- less so, it appeared, on safety, reports CBS News correspondent Jeff Glor.
"Oh boy! You can see him go down and hit the back of the head," an announcer said on TV.
The hit left Keenum seizing his helmet in pain.
"That helmet-to-the-ground is still one of the troubling spots when we talk about concussions at the NFL level," the announcer said.
"So not a bad hit, but that's certainly a very concerning fall to the ground...We see him, difficulty getting up. He's staggering," said Dr. Dennis Cardone, co-director of the Concussion Center at NYU Langone Medical Center.
"For you, these are obvious signs of a concussion?" Glor asked.
"These are clear signs of a concussion head injury and certainly something we would be concerned about," Cardone said.
But Keenum stayed in the game, throwing an errant pass before turning the ball over.
"There is no TV replays on our sideline, and we did not see it on our Jumbotron," St. Louis Rams head coarch Jeff Fisher said. "Had we seen that, we would have taken a different course of action. But we were not aware of that."
The brain is typically protected from light impact by cerebral spinal fluid. But a concussion occurs when a blow to the head causes the brain to hit the skull. After years of scrutiny for its handling of concussions, the NFL issued a new protocol in 2013.
NFL Commissioner Roger Goodell told "60 Minutes" just last week that concussions are down 35 percent since 2012.
"I do believe it's safer but injuries are part of active sports and they are certainly part of football. Football is a contact sport," Goodell had said.
More than two dozen medical staffers are supposed to keep an eye on players during games, including an independent spotter in the press box who has the power to stop the action because of an injury.
The spotter, Fisher said, didn't intervene Sunday because Rams head trainer Reggie Scott was on the field.
"If the trainer's out there tending to a player, then the assumption is that the trainer is going to take care of it... Case said he felt he was OK and then Reggie was told to leave the field," Fisher said.
"The system fell apart a little bit here and we need to fix it," Cardone said.
The Rams said the spotter didn't stop the game because the trainer was on the field. Fisher said the trainer was pulled off the field by an NFL official. No one seems to know anything for certain, except doctors, who after the game officially diagnosed Keenum with a concussion.