Social media reacted swiftly to the unanimous decision by NFL owners that require players and personnel to stand during the national anthem if they are on the field, but gives them the option to remain in the locker room.

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RelatedNFL adopts new policy on national anthem protests

RelatedRoger Goodell's statement on national anthem policy

Teams could face a fine if the new rules aren’t followed.

Commissioner Roger Goodell said the decision is a matter of respect for the flag.

Former 49ers teammates Colin Kaepernick (7) and Eric Reid take a knee during the national anthem in 2016.
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According to ESPN, the NFL  Players Association said it would review the policy and may challenge it if it violates the collective bargaining agreement.

Several players, most notably Colin Kaepernick and Eric Reid, took a knee during performance of the national anthem to protest the killing of African Americans and other minorities by police.

Kaepernick is now a free agent, but no teams have picked him up since he first took a knee in 2016.