Donald Trump just arrived at the annual Army-Navy Football Game ... and to say he did so to a thunderous applause would be an understatement.
The President-Elect showed up midway through the first quarter -- he's got seats in private booth with a protective glass shield -- and fans went nuts. It's unclear who Trump's pulling for, but the Army team prepped him a personal locker ... so maybe they've got a leg up.
Either way ... Army's gonna need any and all support they can get, the team's dropped 14 straight to Navy.