Story highlights He's been critical of athletes kneeling during the National Anthem

His arrival was met with a mixed reaction from fans

Washington (CNN) President Donald Trump walked onto the field and stood with members of the military for the National Anthem at the college football national championship game Monday night in Atlanta. The President stood with his hand over his heart, singing along to parts of the anthem.

The players, as is normal in college football, were not yet on the field for the anthem. The President then smiled and waved as he walked off the field.

The game between the University of Georgia and the University of Alabama was at Atlanta's Mercedes-Benz Stadium.

Trump, who has criticized professional athletes for kneeling during the National Anthem, appeared in good spirits on the field Monday -- and then after the anthem, he left to take his seat for the game.

Hours earlier, in a Nashville speech, Trump again criticized athletes who kneel during the anthem to protest police brutality.

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