President Donald Trump turned the US Open into his own rally ... walking into the stadium to a wave of cheers as the men's championship match was about to begin.
The President strolled into a luxury suite just before 2 PM Sunday -- moments before the men's singles final kicked off -- and fans in the surrounding boxes broke into loud applause as he took his seat. Trump, looking relaxed, waved to the crowd before settling in to watch the showdown on the court.
But his appearance wasn't without controversy because the U.