CLEVELAND — Kyrie Irving gritted his teeth, tightened up his left sneaker and hopped to his feet.
The pain couldn’t stop him. The Boston Celtics couldn’t either.
Irving took over in the second half and finished with 42 points despite playing on a tender ankle, LeBron James added 34 and the Cleveland Cavaliers moved within one victory of an almost inevitable third date in the NBA Finals with Golden State by rallying to beat Boston 112-99 on Tuesday night in Game 4 of the Eastern Conference finals.
With James in foul trouble, Irving was forced to do more than ever and he delivered, scoring 19 in less than five minutes and 33 in a 19-minute stretch.
“The kid is special,” James said. “I was happy to sit back and watch him. He was born for these moments.”
The defending NBA champions, who shot 71 percent in the second half, opened a 3-1 lead in the series and can wrap up their third consecutive conference title — and a “threematch” against the Warriors — with a victory in Game 5 on Thursday night in Boston.
Fighting to keep their season alive, the Celtics aren’t giving an inch despite playing without All-Star guard Isaiah Thomas, who may need surgery for a hip injury.
The Cavs, meanwhile, wouldn’t be on the cusp of the Finals without Irving.
With Cleveland in jeopardy of dropping its second game in a row after James followed an 11-point Game 3 debacle by picking up four first-half fouls, Irving put on a breathtaking one-man show.
Freezing Boston defenders with his dribble and driving to the basket whenever he wanted, Irving made six layups, two three-pointers and a free throw in a dizzying span of 4:48. He capped his blistering 19-point outburst with a three in the final second of the quarter and celebrated at midcourt by pretending to put two pistols back in his holster.
“He saw Bron went out and he wanted to put the team on his shoulders,” Cavs Coach Tyronn Lue said. “He did that.”
Irving said he was driven by the thought of the Cavs seeing their series lead vanish.
“In the back of my mind, I thought, ‘They can’t tie up the series,’ ” he said. “We can’t go back to Boston tied 2-2. We needed everything tonight.”
Irving put a scare into the Cavs and their fans when he stepped on Terry Rozier’s foot and rolled his ankle. He stayed on the floor for a few moments before sitting up and re-tying his sneaker. Nothing was keeping him out.
“It was one of those games we had to fight through and we had to earn it,” he said.
Celtics Coach Brad Stevens was disappointed with his team’s defense on Irving, who was able to spread the floor while surrounded by shooters.
“There’s choices,” Stevens said. “I’m not sure there are good choices. When he gets going like that, he’s tough to stop. The ones we gotta look at are the ones he got at the rim.”
Kevin Love added 17 points and 17 rebounds for the Cavs, now 11-1 in the postseason.
Avery Bradley scored 19 and Jae Crowder 18 for Boston.
Irving did not show any noticeable limp following the game as he walked down the hallway, stopping to hug and kiss friends and family following his performance.
Irving, who has had a history of injuries, said he’s rolled his ankle enough times to know when it’s serious.
“My adrenaline is still going,” he said. “I’m pretty sure I’ll be sore when I get home.”
Crowder and the Celtics are looking forward to going home and redeeming themselves after blowout losses in Games 1 and 2.
“I feel like we’re humble enough to know we haven’t played well at home,” he said. “We want to give our home crowd a better outing than we put out the past two games.”
Lue paused for several seconds before responding to a question about the third and fourth fouls called on James, who was whistled for barely touching Marcus Smart on a jumper and then was called for a charge.
“They called them,” he said of the officials. “We had to do what we had to do.”
Thomas told Stevens that he has visited one hip specialist and plans to see more before it’s decided if he needs surgery. Thomas initially injured his hip in March before aggravating it during the playoffs.
Playoffs glance
All times Central Best-of-7
CONFERENCE FINALS
TUESDAY’S GAME
Cleveland 112, Boston 99
Cleveland leads series 3-1.
THURSDAY’S GAME
Cleveland at Boston, 7:30 p.m.