LeBron James saved the US from what would have been a stunning loss.

James’s layup with eight seconds left was the go-ahead basket on Saturday, and the US Olympic team that’ll soon head to the Paris Games escaped with a 101-100 win over South Sudan in London, rallying from a 16-point deficit to avoid perhaps the biggest upset in the program’s history.

“[It was] a good reminder that when we play against teams, it’s the biggest game of their lives,” US coach Steve Kerr said. “We have to expect everyone to play like that.”

South Sudan, the African nation that gained its independence just 13 years ago and is about to play in the Olympics for the first time, led for more than half the game and had a chance to win at the end. But Carlik Jones’ runner off the glass missed with four seconds left, and the US eked out a victory.

“I’m going to be honest: I like those better than the blowouts,” James said as he walked off the court. “At least we get tested.”

Down by 16 at one point, the Americans dug out of that hole with an 18-0 run in the second half – then needed heroics at the end to stave off South Sudan’s reply. JT Thor’s three-pointer with 20 seconds left gave South Sudan a 100-99 lead, then the US called timeout and handed the ball to James.

He made it look easy: He waited then drove and laid it in with ease to put the US back on top. James finished with a game-high 25 points, six rebounds and seven assists for the US, who improved to 4-0 with one game left – Monday against World Cup champions Germany – on their pre-Olympic exhibition tour. Anthony Davis added 15 points and 11 rebounds.

Marial Shayok had 24 points for South Sudan and Jones had a triple-double – 15 points, 11 rebounds and 11 assists.

The teams will meet in group play in the Paris Olympics on 31 July.

“It’s basketball. It happens,” Stephen Curry said post-game. “You want to play perfect every game; it doesn’t happen. But can you dig deep and do the little things that help you win? Offense can come and go, but defense is the thing that helps you win championships, medals, all that stuff.”

It should have been a mismatch, and for the first half, it was – just not in the way anyone would have expected. The US roster has 12 players, all of them All-Stars or NBA champions or both, with a total of 189,038 points in their regular-season careers, with 7,832 combined starts. South Sudan have four players who have appeared in an NBA game. They’ve scored a combined 1,228 points and started 19 games.

It didn’t matter. It was 8-0 to the US after three minutes. South Sudan then outscored the US by 24 points in the remainder of the half. The US allowed South Sudan to shoot 61% in the first half and were outscored 21-3 from deep in the opening 20 minutes.

US coach Steve Kerr said the team were “embarrassed” at half-time. “What we’ve learned with USA basketball is that the game has closed,” Kerr said post-game. “The game has gotten better across the globe.”

Kerr pointed to the team’s poor preparation for the slow first half. “I did not do a great job preparing our team,” Kerr said. “We did not focus enough on what they’re capable of, and that’s on me. I think that really allowed South Sudan to gain confidence early. They were great. They played a wonderful game and the ending was good for us, just to feel that, to feel what it’s going to be like in Paris and Lille.”

An 18-0 run in the second half – James involved in most of it – was what really saved the US, turning a 76-65 deficit into an 83-76 lead. South Sudan led by 16 late in the first half – 58-42 – before the Americans got the last basket to cut the deficit to 14 at the break.

But the 18-0 run was key. James had four assists during the spurt and Curry, from about 35ft, connected on a 3-pointer late in the third that gave the US their first lead since the first quarter at 79-76.

Wenyen Gabriel banked in a three-pointer to get South Sudan within 85-84, but James – his former teammate with the Los Angeles Lakers – connected from behind the arc on the ensuing US possession, and the US eventually pulled through by the slimmest of margins.

“Today we were able to represent our country with pride and we put up a good fight and showed the potential of our country,” Gabriel said. “I think it was a proud moment for a lot of people.”

Davis said the team got to the arena late, thrown off by standstill London traffic, and that routines going into the game were disrupted. But South Sudan showed the US that nobody at the Olympics will concede anything to the four-time defending gold medalists.

“The match was super important because we feel like we can’t be beaten and they showed us we can be beat,” Anthony Edwards said after the game. “We have to come ready to play.”

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