The US men's basketball team sang 'happy birthday' to Kerri Walsh-Jennings after she won a huge beach volleyball match

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Members of the US men's basketball team used their night off on Sunday night to check out some other Olympic events and cheer on their Team USA compatriots. 

Draymond Green, Jimmy Butler, DeAndre Jordan and Kevin Durant first checked out Usain Bolt's historic victory at the Olympic Stadium, and then headed over to Copacabana Beach to watch American beach volleyball duo Kerri Walsh-Jennings and April Ross take on Australia in a quarterfinal elimination game. 

Walsh-Jennings and Ross won, 2-0, but their game didn't finish until well past midnight. That didn't bother the basketball team, though, as the crew of basketball stars stayed until the end - and then proceeded to lead a "Happy Birthday" singalong to Walsh-Jennings, who had turned 38 after the clock hit midnight. 

Here's video of the nice little gesture:

The NBA stars seemed to be having fun in the stands all night long. Here they are dancing and busting out their best air guitars:

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This isn't the first time we've seen Durant, Green, Butler and Jordan enjoying themselves as Team USA fans in Rio, either. Last week, they made their way to the aquatic center to watch Michael Phelps and Katie Ledecky both win gold. They all took pictures together afterwards, making Phelps look unusually scrawny. 

It's great to see the NBA stars cheering on the other American Olympians, especially at beach volleyball - a sport markedly less popular than theirs. 

The basketball team, meanwhile, plays in the quarterfinal on Wednesday. Their opponent is not yet known.