The NFL's national anthem protests have persisted, and NFL owners are getting restless. Between an ongoing feud with President Donald Trump and more and more fans speaking out against the protests that have taken place, the NFL has been put in a difficult position.

On Tuesday, commissioner Roger Goodell sent a letter out to NFL executives, advising them on the controversy. ESPN's Adam Schefter posted a full copy of the letter that ESPN obtained.

The NFL has oscillated a lot regarding their stance on players kneeling. While the league as an entity has steadfastly said that it would prefer that players would stand united, it has also acknowledged that players have the right to protest during the anthem.

NFL owners have been perturbed by the fan response, and have started giving players ultimatums regarding the anthem. Jerry Jones told players to stand during the anthem or sit during the game, whereas Adam Gase and the Dolphins told players to stand or stay in the locker room until game-time.

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