The Hawks were determined to let anybody other than LeBron James beat them.

So J.R. Smith did.

The Cavaliers guard came off the bench and lit up the Hawks for 28 points in a 97-89 victory in Game 1 of the Eastern Conference finals Wednesday night at Philips Arena. Smith was 10 of 16 from the field, including 8 of 12 from 3-point range, in the impressive performance.

The Cavaliers took a 1-0 lead in the best-of-seven series after stealing home-court advantage from the top-seeded Hawks. Game 2 is scheduled for 8:30 p.m. Friday in Atlanta.

The Hawks suffered a severe blow when DeMarre Carroll suffered a left knee injury on a drive to the basket following a steal with 4:59 remaining. He appeared to be hurt planting for a layup. He immediately grabbed his left knee when he hit the floor and was in pain. After several minutes he was helped by two teammates to the Hawks locker room unable to put any weight on his left leg.

Following the game, the Hawks announced that Carroll suffered a left knee sprain and would have an MRI exam Thursday. The diagnosis could be updated pending the results of the test.

“That was a tough one,” Kyle Korver said. “We love DeMarre like a brother. To see him go down, we’ll see how he is tomorrow. Obviously, it didn’t look good.”

The Cavaliers won the game with a 22-4 run between the third and fourth quarters, including an 11-0 run to start the final period, to go up by 18 points. Smith had five 3-pointers as the Cavaliers broke open the game that was tied at 63-63.

“Reflecting back now, without going through the film, he did make a handful of tough shots,” Hawks coach Mike Budenholzer said. “But he is a shooter. He is somebody who can get hot. He was a priority coming into the game, and I think we can do a better job and not have any breakdowns going into the next game.”

James finished with a game-high 31 points for the East No. 2-seeded Cavaliers, who held a 49-36 rebound advantage. Kyrie Irving was limited to 10 points and six assists. Tristan Thompson (14 points, 10 rebounds) and Timofey Mozgov (10 points, 11 rebounds) finished with double-doubles.

Jeff Teague led the Hawks with 27 points. Al Horford scored 16 points, and Paul Millsap added 13 points. The Hawks were a dismal 4-of-23 from 3-point range.

“The shots weren’t falling,” Teague said of the Hawks’ 3-point woes. “We missed some easy ones, some wide-open 3s. Guys were open. We just didn’t capitalize on the shots tonight.”

The Hawks used a 13-1 run to pull within four points, 91-87, with 55 seconds left. James ended the run with a drive and dunk. The Cavaliers wrapped up the game at the free-throw line.

If Carroll is out for an extended period of time, the Hawks face a series without their primary defender on James.

“He is such a great teammate, and everybody is concerned for DeMarre,” Hawks coach Mike Budenholzer said. “We’re hoping that he is healthy and ready to help us as soon as possible. That’s how we feel about each of our teammates, each of our players.”

The Hawks led by as many as nine points in the first quarter, but led only 26-20 after the period despite shooting 61 percent (11-of-18). The Cavaliers shot just 35 percent (8-of-23) but held a decisive rebounding edge, 15-6 overall and 7-0 on the offensive glass.

The Cavaliers came all the way back and took a two-point lead, 35-33, with a 15-5 second-quarter run. Smith had nine points in the run with three 3-pointers. The Hawks answered with six consecutive points and neither team led by more than four points the rest of the half. The score was tied at 51-51 at intermission.

Teague led the Hawks with 17 first-half points on 7-of-12 shooting, including four scores driving to the basket.

The Cavaliers went up by as many as eight points in the third quarter as Smith hurt the Hawks again from long range. He made back-to-back 3-pointers in an 8-0 run. The Cavaliers took a 74-67 advantage into the final quarter after the Hawks shot only 23.5 percent (4-of-17) in the period.

“There was a stretch early in the fourth quarter where they were able to create a little separation and lead,” Budenholzer said. “A few things happened during that time that we’ve got to do better. I think if we continue to attack, play with pace and move the ball better, I think that is going to give us our best chance going into Game 2.”