This already happened in the NBA in 1996:
"Rather, he comments that many American Muslims are still sorting out their beliefs. Denver Nuggets guard Mahmoud Abdul-Rauf, who created a small stir last year by sitting during the US national anthem, "misunderstood" Islam, Olajuwon says. "The advice he got was not the best advice. He took things to an extreme, whereas Islam is a flexible faith, giving you a lot of choices."
I can't find it as a direct quote but I believe Olajuwan said that as a Muslim should stand for the flag out of respect for the country you are in even if you disagree with things that the government does or something to that effect.