FOXBOROUGH, Mass. -- Gisele Bundchen’s remarks Wednesday on “CBS This Morning” that her husband, New England Patriots quarterback Tom Brady, suffered a concussion in 2016 and that he's had others have sparked a conversation on a hot-button topic with multiple layers.

The Patriots’ injury reports from 2016 and earlier have since been analyzed, and Brady never has been listed with a concussion in his 17 years with the team.

The Patriots declined to comment on the report, and Brady's agent did not respond to a request for comment. Brady also has not commented at this time. Later on Wednesday, the NFL issued a statement, which said in part, "There are no records that indicate that Mr. Brady suffered a head injury or concussion, or exhibited or complained of concussion symptoms."

The NFL Players Association will look into the matter, which is standard protocol.

In Bill Belichick’s 18 years as Patriots head coach, hardly a week has gone by during the season without him commenting on the importance of players' health to the team. Concussions are obviously a significant part of that concern.

The NFL’s concussion protocol has been evolving, with independent medical officials placed on sidelines during games. Those officials have the authority to pull players who shows signs of a concussion. That happens most often on obvious hits. This setup takes concussion reporting out of the team’s or player’s hands during games.

But concussions also can happen on less obvious plays, even in practices, and there are times when the onus falls on players to report symptoms of a concussion. Once a player does that, there is an league-specified protocol that all teams must follow.

So, from a big-picture standpoint, it's possible that several teams around the NFL have players who have suffered unreported concussions because the player didn't report it to the medical staff himself.

It is not clear whether Brady ever has reported symptoms of a concussion to the team.