A gut-wrenching loss in the NBA Finals opener has the Cleveland Cavaliers vowing a game-two fightback Sunday while the defending champion Golden State Warriors cope with two injured starters.

Host Golden State seized a 1-0 lead in the best-of-seven championship series with a 124-114 overtime triumph that Cleveland coach Tyronn Lue called a robbery, one the Cavs vowed Friday to put behind them quickly.

“We lost a tough game,” Lue said. “We can’t dwell on that. We can’t live on that or we won’t be able to perform in game two. So we have to get on with it.

“Listen, we’re not broken. We lost a game. It was a tough game for us. The guys’ confidence is not shaken. We have the blueprint. Now we have to execute at a higher level.”

That confidence flowed to Cavs guard George Hill, who spent a sleepless night after missing a late free throw that would have put the Cavaliers ahead.

“We can win this series playing the right way. Everyone in this locker room felt we gave one away but we have a game on Sunday to make up for it and get back on the right track,” Hill said Friday.

“None of us is demoralized. We’re going to bottle up all that frustration from game one and bring it out for game two.

“We’re the last two teams standings. We’re going to fight it out. It shouldn’t be a prom dance. It’s going to be a fight.”

The Warriors, seeking their third title in four seasons from an unprecedented fourth consecutive finals showdown with the Cavs, expect nothing less.

“I don’t expect them to be deflated by Sunday. I expect them to play with great energy out of the gate Sunday,” Warriors guard Klay Thompson said. “If we play with great passion and great focus I think we’ll be fine.”

Cleveland superstar LeBron James had a playoff career-high 51 points, the most in the finals since Michael Jordan a quarter-century ago and the most in the finals in a losing cause.

“He did everything he could to will our team to win,” said Lue, who was asked if James could play better and said, “I hope so. I know it’s asking a lot but he needs to lead by example. He needs to keep it up.”

Warriors coach Steve Kerr wants tougher defending on James.

“Overall we did not do a good job on LeBron. He got to spots he wanted to. It’s a team-wide focus and aggression that needs to change,” Kerr said.

“I didn’t think we got him out of any sort of comfort zone and we’ve got to do a better job of that on Sunday.”

Iguodala ‘doubtful’

Golden State’s Stephen Curry scored 29 points with nine assists, Kevin Durant added 26 points and nine rebounds and Thompson added 24 points.

The Warriors have two injured starters, with Andre Iguodala having missed the past four games with a bruised left leg.

“He has done some work. He’s feeling a little bit better,” Kerr said. “I would just call him doubtful for game two. We’ll see how it goes.”

Thompson suffered a left leg injury early in game one but vowed to play through pain.

“Sore but nothing too bad,” Thompson said. “I knew it would be sore but luckily we have a couple days between games so it will get right.

“If this was game 32 of the season, I would not have played.”

The NBA released its review of late-game referee calls and stood behind the reversal of a call from a charge on Kevin Durant to a James blocking foul.

‘This one hurt bad’

It also showed Green committed a lane violation on the free throw Hill missed that would have put the Cavs ahead with 4.7 seconds to go in the fourth quarter.

“I stayed up most of the night rewatching the free throw, rewatching the play. I went over it in my head again and again,” Hill said. “I have great teammates in my ear all morning telling me to forget about it move on and don’t let it linger.”

Hill called it his most disappointing defeat in his 10-year NBA career.

“This one hurt bad,” Hill said. “Me not hitting that free throw cost the team the game but I dealt with it last night and we have to move on.”