The NFL approved a rule on Tuesday that allows an off-field official to call a medical timeout if a player shows symptoms that warrant evaluation under the league's concussion protocol.

The new rule comes after New England Patriots wide receiver Julian Edelman looked dazed after a helmet-to-helmet hit during the Super Bowl and stayed in the game.

There are independent certified athletic trainers at NFL stadiums on game day who help both team medical staffs identify players in need of evaluation. With a vantage point in a booth above the field, they can now stop the game and communicate with on-field officials if a player appears disoriented.

"We do not expect this to be a rule that gets used a lot," said Atlanta Falcons president Rich McKay, chairman of the NFL competition committee. "We expect it to be a fail-safe when people just don't see this player and the distress the player may have had."

The trainers in the booth, who have access to video replay and multiple angles of a specific play to identify possible head injuries, have previously communicated with team trainers and doctors on the sidelines under NFL concussion protocol.

The change was one of a series of safety enhancement rules approved by the NFL at its league meetings in Phoenix.

Bears sign McDonald

The Chicago Bears have agreed to a one-year contract with former San Francisco 49ers defensive end Ray McDonald.

Bringing in McDonald, who played under new Bears defensive coordinator Vic Fangio in San Francisco, could be controversial for Chicago given his issues with the law.

The 49ers cut McDonald in December after a woman accused him of sexually assaulting her following a night of drinking in which she injured her head in a fall by his swimming pool.

The team also announced a one-year deal with defensive end Jarvis Jenkins, who spent the last four years with the Washington Redskins.

Long arm of the law

He might be taking his talents to the nation's capital, but former San Francisco 49ers cornerback Chris Culliver could still have some residual obligations in the Bay Area in connection with a hit-and-run incident last year.

Over the objection of the Santa Clara County District Attorney's Office, a judge agreed Tuesday to reduce a felony charge for possession of brass knuckles to a misdemeanor for Culliver, who earlier this month signed a four-year deal worth up to $32 million with Washington. Culliver still faces one count of misdemeanor hit-and-run for the same incident.

Peterson, Vikes at odds

Adrian Peterson and the Minnesota Vikings have reached a standstill in their relationship.

Peterson's agent, Ben Dogra, said in an interview Tuesday that he believes a return to Minnesota this season is not in the "best interest" of the standout running back.

Peterson previously expressed uneasiness about continuing to play for the Vikings, but Dogra has advanced that stance to the point of wanting out. General manager Rick Spielman has told Dogra the team doesn't plan to release Peterson, who turned 30 on Saturday.