CLEVELAND -- With LeBron James limited because of four first-half fouls, Cleveland Cavaliers point guard Kyrie Irving seized the role of leader and proved to be an impactful player against the Boston Celtics in Game 4 of the Eastern Conference Finals at Quicken Loans Arena Tuesday night.

Irving set a single-game career high with 42 points on 15-of-22 shooting, including a four-for-seven mark from three-point range, which helped the Cavaliers overcome a 16-point second-half deficit on the way to a 112-99 victory and 3-1 lead in the best-of-seven series.

“It was one of those games that we had to fight through, and we had to earn it,” Irving said. “You know, that Boston Celtics team is coached well, very well-coached, and they gave us everything [they] had, and we had to withstand some runs, and in the third and fourth quarter, we were able to withstand them and create a separation for ourselves.”

Down by 12 in the early part of the third quarter after a Celtics basket, the Cavaliers slowed chipped away at the deficit with Irving and James at the forefront of the comeback effort.

After Irving made a driving layup, James buried a 17-foot jump shot. Then, James caught a pass from Irving and threw down a slam dunk that brought the crowd to its feet and got the Cavaliers to within seven points, 61-54, with 8:42 to play in the third quarter.

Later in the period, Irving made two straight driving layups in the lane to put the Cavaliers up by five points, 77-72, but on the second shot, he fell to the floor and reached for his lower left leg. However, after retying his left shoe, Irving jogged down to the defensive end, and hit a driving jump shot on the next possession.

“I'm just thankful,” Irving said. “I’ve twisted my ankle so many times that on plays like that, you have two choices, either you can sit there and kind of wallow in the sorrow of you twisting your ankle or capture the moment, and my adrenaline is still going at this point.

“I'm pretty sure when I get home, my body will probably hate me, but it's the magnitude of the moment and what's at stake, and I wasn't coming out for any margin. I wasn't coming out. I knew how much we needed this game and how much my teammates needed me and the importance of me leading these guys as well as ‘Bron.”

Following the near heart-stopping moment for the 20,562 fans that packed inside Quicken Loans Arena, Irving completed a three-point play with 1:02 left in the third quarter, and then, beat the buzzer with a deep three-pointer.

“The importance of a Game 4, especially the way we came out in Game 3, you know, in the back of my mind, I was like, I'm saying to myself, ‘They cannot tie up this series. They cannot. We cannot go to Boston 2-2, and then, it becomes almost an even series,’” Irving said.

“For us, our focus level has to be at an all-time high, and the little things that matter, that's going to make the difference within the game, you saw Kevin doing it, being a man down low. Tristan, J.R. giving us some great minutes, Richard Jefferson, Deron, Kyle, everybody's effort, we needed everything tonight, and we all need that from one another in order to be a great team, especially for what we're trying to accomplish.”