– J.R. Smith knocked down a tough three-pointer, then another. Turning toward the fans, their heckling transformed to groans, he blew off his right index finger and motioned toward his side, like he was holstering his pistol.

Yep, Smith was that hot.

While LeBron James led Cleveland with 31 points, it was Smith who ignited the Cavaliers in Game 1 of the Eastern Conference finals. He made eight three-pointers and scored 28 points in a 97-89 victory over the top-seeded Atlanta Hawks on Wednesday night.

"When he gets hot," Cleveland coach David Blatt said, "he gets smoking hot."

Intent on bringing Cleveland its first NBA title, James sealed the victory with a soaring dunk in the final minute.

For the Hawks, it was the second consecutive series in which they've lost the opening game at home. Game 2 is Friday night.

Making matters worse for Atlanta, DeMarre Carroll went down with a knee injury driving to the basket with 4:59 left. He was helped to the locker room, not putting any weight on his left leg, and will undergo an MRI on Thursday.

Besides being the main defender on James, Carroll had been the Hawks' leading scorer in the playoffs. He was averaging more than 17 points coming into Atlanta's first conference final.

"DeMarre is a complete player," Hawks coach Mike Budenholzer said. "He has a big impact at both ends of the court."

Jeff Teague led Atlanta with 27 points. But Atlanta didn't produce its usual balanced scoring, as two starters — Kyle Korver and Carroll — failed to reach double figures.

With Smith doing most of the damage, Cleveland outscored the Hawks 22-4 over the final five minutes of the third quarter and the first two minutes of the fourth. During that span, he made five three-pointers and another jumper from just inside the arc, as well as throwing up a lob that Tristan Thompson dunked.

Smith has been a huge addition for the Cavaliers since he was acquired in January as part of a three-team trade with New York and Oklahoma City. A player once known for his selfishness, he had learned to fit in.

When the Cavaliers really needed Smith in Game 1, he seemed to make every shot.

"Once I start shooting," Smith said, "everybody keeps telling me to keep shooting."

Cleveland scored the first 11 points of the final period — all but two on threes by Smith — for its biggest lead, 85-67.

Carroll's injury silenced the raucous crowd. While he was being taken off, James came over to say a few words and pat the injured player on the head.

"We're all a brotherhood," James said. "You don't want anybody to get hurt like that."

Even without Carroll, Atlanta closed to 91-87 with about a minute remaining. But James' dunk finished the Hawks.