A hobbled LeBron James hit the go-ahead three-pointer with 2:51 to play as the Miami Heat rallied to beat the Oklahoma City Thunder 104-98 to move within one victory of the NBA title.
James had 26 points, 12 assists and nine rebounds, while Dwyane Wade and Mario Chalmers each scored 25 points for the Heat -- who took a 3-1 stranglehold on the best-of-seven championship series.
"Four or five plays, that's what this series is coming down to," said Miami coach Erik Spoelstra. "That is what this game came down to.
"This is competition at its fiercest."
The Heat, who won the title in 2006, can win their second championship in franchise history with a victory in game five on Thursday in Miami.
With James on the bench suffering from bad leg cramps in the fourth, Chalmers helped secure the victory with a layup with 44 seconds left that made it 101-96.
The victory spoiled a brilliant offensive performance by Thunder guard Russell Westbrook, who finished with a game-high 43 points.
Kevin Durant had 28 points for the Thunder, who got off to their best start of the series in the first quarter but couldn't execute as well as the Heat down the stretch.
"They made a few extra plays down the stretch," said Thunder coach Scott Brooks. "Experience has nothing to do with it. We never use that as an excuse.
"LeBron came back in after his injury and made a great play, made a tough three, and they made some plays at the end."
James nailed a three-point shot to break a 94-94 tie late in the fourth. The basket came about a minute after he had re-entered the game, having injured his left thigh earlier in the quarter when he slipped on a drive to the basket.
He sat out for just over a minute the first time he hurt the leg, returned to action and sank the crucial three pointer. He then had to be helped to the bench a second time and stayed there for the final minute of the game to get treatment from the trainers while his teammates closed it out.
Spoelstra said James's problem wasn't serious but it caused him a lot of pain in the final minutes of the fourth and he couldn't risk leaving him out there.
"LeBron had cramps," Spoelstra said. "We talked about playing with an intensity until you had nothing left by the end of the game and he did. It was warm in the building. He just had some cramps at the end."
It was a physical contest with huge momentum swings in the first half as the Heat had to overcome a 17-point deficit in the first quarter.
Westbrook was the catalyst for the Thunder, scoring 17 points in the fourth, including 13 straight Oklahoma City points during one stretch in the final quarter to keep the score close.
With Westbrook igniting the offence, the Thunder had stormed out of the gate by shooting 62 percent from the floor in the first quarter. Westbrook scored 10 points as the Thunder led 33-19 at the end of the period.
Wade and James answered for the Heat, pacing the attack in the second as the Heat went on a 13-0 scoring run to the start the quarter and tied the game 35-35 in the first four minutes.
Miami never led in the second quarter but they closed the gap to 49-46 at the intermission with the help of seven points by Wade and James who almost had a triple double at halftime.
After their blazing start, the Thunder shot just 30 percent from the field in the second quarter.
The Thunder finished off the scoring in the third quarter with a three-point play to cut the Heat lead to four, 79-75. With just three seconds left, Westbrook hit a jumper and Durant was fouled in the paint then made the free throw.
"We were just trying to stay in attack mode," Westbrook said. "Shots were falling. But it really doesn't mean nothing. We didn't come out with the win."
For the first time since game one of the series, Durant wasn't in foul trouble in the third. He had just two fouls heading into the final quarter so was able to stay in the game during key stretches in the third as the Thunder kept the score close.