Irving stepped on Terry Rozier’s foot, then landed awkwardly after a layup with 1:47 remaining in the period. That induced the usual quick-trigger panic from Quicken Loans Arena. With trainers surrounding him, Irving could have gone to the sideline and had that left foot checked out. Instead, he simply got up and walked to the other end of the court. That induced the usual quick-trigger applause.

GAME CENTER: Celtics-Cavaliers Game 4 stats 

“I’ve twisted my ankle so many times,” Irving said. “You have two choices. You can either dwell on the sorrows of twisting your ankle or you can capture the moment.” 

Irving made the second choice. He caught a quick-hit pass for a layup on the next possession. He added an and-one layup next. Then a jumper. Then a 3-pointer with 0.5 seconds to go that capped a 40-point quarter for the Cavs and helped generate a 112-99 Cleveland victory.  

Irving had 39 of his postseason career-high 42 points at that point, part of a ridiculous three-game stretch in which he’s 33 of 48 — or 68.8 percent – from the floor. That includes a 15-of-22 shooting effort in Game 4 that helped give the Cavaliers a commanding 3-1 lead in the series, which returns to Boston for Game 5 on Thursday.

Taking over the third quarter wasn’t even the most important role Irving played Tuesday. LeBron James picked up his fourth foul with 6:46 to play in the second quarter and went to the bench. Cleveland was trailing by 10 points at the time. Irving’s steady hand kept that deficit from getting out of control. 

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“I thought he saw LeBron went out and he wanted to put the team on his shoulders and on his back and let the team ride him until LeBron got back,” Cavaliers coach Tyronn Lue said. “He did that.”

What did he show James?

“Nothing,” James said with a smile. “Same thing I’ve been saying since I got here. I’ve been saying he’s a special kid and a special talent. As the stakes get higher and higher, his game gets higher and higher. It’s not a surprise.” 

Irving scored nine points over that crucial stretch, and Cleveland trailed 57-47 at halftime — the same 10-point margin as when James left.

“The importance of Game 4, especially the way we came out in Game 3,” Irving started before finishing what he was thinking during that stretch. “In the back of my mind I’m saying to myself, ‘They cannot tie up the series.’”

Irving then took over with his dominant 21-point third quarter. That went well with James, who finished with 24 points in the second half.

MORE: Celtics vs. Cavaliers Game 4 highlights

“Irving again, end of the second, end of the third, did some incredible things with the ball,” Celtics coach Brad Stevens said before doling out more praise for Irving. “We had really good athletes, quick guys that make things tough on people guarding him, and he was able to raise up and make a lot of tough shots.” 

Irving capped off his night by switching hands for a layup between two Boston defenders in the closing minute. 

For Lue, the performance wasn’t a surprise, either. For Stevens, it was a “tip-of-the-cap” moment. For the Cavs, it meant the Big Three were in business. Kevin Love added 17 points, and Irving’s play showed Cleveland could withstand a four-foul first half from its superstar. The latter is exactly what this team needs in a potential Finals three-match against the Warriors and for the foreseeable future.

Game 4 made one other thing clear: Irving should be up to whatever challenge comes next in his role as, in his words, “an observer and a leader.” 

“Adversity has a way of really bringing out the best people or it can bring the worst,” he said. “I’ve been on both sides … You just have a choice to make, and it has to be a fearless approach. I’m not going to waver or show any signs of giving up.”