Independent medical observers stopped NFL games five times in 2015, the first season in which the ''Medical Timeout'' was employed as a method to identify players who had suffered major injuries or possible concussions.
In its 2016 Health and Safety Report, released Tuesday, the NFL said an average of 29 health care providers attend games, many of whom can rule a player out due to a concussion.
Last season, the NFL stationed athletic trainers in spots high above the field and allowed them to watch replays and to call timeout if they saw injuries that otherwise went unnoticed.
Rams quarterback Case Keenum stayed on the field after his head slammed to the turf near the end of a game last season, spurring questions about how well the new rule worked.
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