LeBron James saved the US from a crushing defeat.

James’ layup with 8 seconds left was the deciding basket on Saturday, and the U.S. Olympic team, soon to be in Paris, beat South Sudan 101-100 in London, overcoming a 16-point deficit and perhaps preventing the biggest upset in program history.

South Sudan, the African country that gained independence just 13 years ago and is making its first Olympic appearance, led for more than half of the race and had a chance to win near the end. But Carlik Jones’s runner from the glass missed with about four seconds left, and the Americans survived.

“I’ll be honest, I like those better than the blowouts,” James said as he walked off the field. “At least we’re getting tested.”

Oh, they were tested — by a team that entered the game as 43.5-point underdogs, according to BetMGM Sportsbook.

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

At one point, they trailed by 16 points, but the Americans emerged from that hole with an 18-0 second-half run — and it still took some heroics at the end. JT Thor’s 3-pointer with 20 seconds left gave South Sudan a 100-99 lead, at which point the Americans called a timeout and gave the ball to James.

He made it look easy: he waited, waited, waited, drove and put it in with ease to get the US back on top, and eventually the Americans got the stop they needed.

James finished with a game-high 25 points, six rebounds and seven assists for the U.S., which improved to 4-0 with one game remaining — Monday against world champion Germany — on its pre-Olympic exhibition tour. Anthony Davis added 15 points and 11 rebounds for the Americans.

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

The teams will play a group match on July 31 at the Olympic Games in Paris.

“It’s basketball. It happens,” U.S. guard Stephen Curry said. “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 and all that stuff.”

It should have been a mismatch, and in the first half it was — just not in the way anyone expected.

The U.S. roster features 12 players, all All-Stars or NBA champions or both, who have totaled 189,038 points in their regular season careers, with 7,832 combined starts. South Sudan has four players who have appeared in an NBA game. They have scored a combined 1,228 points and started 19 games.

Didn’t matter. It was 8-0 US after 2 1/2 minutes. Rest of half: South Sudan 58, US 34. The Americans allowed South Sudan to shoot 61% in the first half and were outscored 21-3 from 3-point range in the first 20 minutes.

“I didn’t prepare our team well,” Kerr said. “We didn’t focus enough on what they can do, and that’s my fault. I think that gave South Sudan confidence early on. … They were great. They played a great game and the end was good for us, just to feel that, to feel what it’s going to be like in Paris and Lille.”

An 18-0 second half run, with James involved for most of the game, was what really saved the US, turning a 76-65 deficit into an 83-76 lead.

South Sudan led by 16 points at the end of the first half – 58-42 – before the Americans scored the final goal to reduce the lead to 14 points at halftime.

But the 18-0 run was crucial. James had four assists during the spurt and Curry, from about 35 feet, sank a 3-pointer late in the third period to give the U.S. its first lead since the first quarter, 79-76.

Wenyen Gabriel scored a 3-pointer to bring South Sudan back to 85-84, but James, his former Los Angeles Lakers teammate, scored a 3-pointer on the ensuing American possession, and the Americans would eventually pull ahead by a very narrow margin.

“Today we were able to represent our country with pride and we fought a good battle 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 arrived at the arena late, confused by gridlocked London traffic, and pre-game routines were disrupted. That may be true, but South Sudan showed the U.S. that no one at the Olympics will give in to the reigning four-time gold medalists.

“It doesn’t matter how close the game is,” James said. “We went out there to get better.”

— Tim Reynolds, AP basketball reporter