Nigeria vs. Team USA Basketball
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The U.S. men's basketball team started its Olympic exhibition slate on Saturday, and it didn't go well. In one of the most stunning international upsets in history, Nigeria defeated Team USA 90-87 in Las Vegas. This was Team USA's first ever loss to an African nation. Team USA is now 54-3 in exhibition games since 1992. 

Kevin Durant led Team USA with 17 points, but couldn't find his shot and went just 4-of-13 from the field. Meanwhile, Jayson Tatum went for 15 points and seven rebounds, and Damian Lillard added 14 points and four assists. Overall, Team USA had a poor shooting night, going 26-of-63, just 41% on the night. 

Trailing by three points in the closing seconds, they had a chance to tie the game, but couldn't execute the play that was drawn up during their timeout. It took far too long to develop, and Nigeria eventually fouled to prevent the Americans from even getting up a 3-point attempt. 

If you want some context as to what constitutes calling this an all-time upset, look at the result when these two countries played at the 2012 Olympics in London:

After the London Games, the U.S. and Nigeria met again in 2016 for an exhibition, and the U.S. won by 44 (110-66).

On Saturday, Nigeria -- which is being led by Warriors assistant coach Mike Brown -- took the common route to pulling off a massive upset: it got scorching hot from 3, hitting 20-of-42 triples and never trailing in the fourth quarter. Gabe Vincent, of the Miami Heat, hit six of those 3s en route to a team-best 21 points. Nigeria also won the rebounding battle 46-34. 

You would think this would get Team USA's attention as it continues to prep for the start of the Olympics in Tokyo. We'll see if this lights a fire when the U.S. gets back on the court for its next exhibition on Monday vs. Australia. After the loss, that's the approach Jayson Tatum and head coach Gregg Popovich were taking. 

"In a way, I'm kind of glad it happened," Popovich said. "That means nothing if we don't learn from it. It could be the most important thing in this tournament for us."

"I think this is good for us," Tatum added. "We are going to learn a lot from film, regroup and stay positive."