President Donald Trump faced loud booing from Madison Square Garden fans Monday night during the national anthem at Game 3 of the NBA Finals. As the first sitting U.S. president to attend an NBA championship game, Trump drew immediate disapproval when displayed on the arena’s jumbotron. Shielded behind bulletproof glass, the president smiled as the jeers echoed throughout the venue.

Security was heavily tightened for the event. Metal detectors, extended perimeter lines, and a bag ban delayed thousands of ticket holders for hours. Trump arrived via helicopter and motorcade, watching the matchup from Knicks owner James Dolan’s suite alongside his granddaughter, Kai Trump, and several cabinet officials.

The San Antonio Spurs defeated the New York Knicks 115 to 111, halting the home team’s 13-game playoff winning streak. Game 4 is scheduled for Wednesday. Trump later told reporters he perceived the crowd’s reaction as enthusiastic cheers. This marks the second recent sporting event where the president encountered a polarized audience, following a mixed response at an NFL matchup last November.