Former presidents Bill Clinton, George W. Bush, and Barack Obama all stood and put their hands over their hearts during the national anthem at the open of The Presidents Cup golf tournament Thursday.

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The moment was the first public appearance for the group of former presidents after NFL players ignited controversy by kneeling or locking arms during the anthem. President Trump called on NFL owners to fire players who would not stand for the anthem.

Kneeling before the anthem started last season with former-San Francisco 49ers quarterback Colin Kaepernick, who claimed to be protesting police brutality.

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As the Golf Channel announcer noted in the broadcast of the Presidents Cup, the national anthem is not usually played before golf matches.

“Everyone around obviously stopped for a moment to honor our country. The national anthem in sports has been in the news… It rarely gets played at golf events,” he said.

“The [U.S.] captain indicated that no protest of any kind would happen here,” the announcer said. “The players stopped their warm up routine, hats off, hands on heart, national anthem sung.”

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