The NFL Commissioner is going to order the players to stand for the national anthem.

[JoeStuckInOH]

110. They could possibly fine players, too.

It ultimately depends on what's in the contracts, but if the team decides to sit or cut a player there is generally a portion of the contract that is guaranteed to be paid out. Many players have incentive based pay built into their contracts. Even if you don't fine them, simply benching a player that expects to see significant game time hurts their overall salary and it can be punitive in that manner.

I would expect, being an off-field violation, there will be fines imposed by the NFL and then suspensions for multiple-offenders. And if the league says failure to comply means missing games... well, coaches and general managers don't want to deal with uncertainty in the roster and will trade players away or let contracts expire. Many coaches and managers don't care whether a player stands or not, but when suspended players start affecting game strategies and impacting team competitiveness... then players at risk for suspension will find themselves sitting next to Colin Kapernick on Sundays in the near future.

While I believe the players DO have a right to comment and protest social injustices and should be able to do so WITHOUT reprisal... I also believe the NFL and Teams have a right for their events to remain apolitical and not be used as a soap-box unrelated to the sport itself.