BOSTON - Amir Johnson began Friday's game between the Celtics and Hawks with a three-pointer.

It turned out to be a sign of things to come.

Not only did Johnson follow that up with two more points from the free throw line for Boston's first five points, but he'd go on to score 17 on the night to go with eight rebounds, four assists, three steals, and three blocks.

It was the type of game everybody was waiting to see from Johnson, who combined for 18 points in the four games prior to Friday night. It wasn't that Johnson was missing his shots in those other games - he just wasn't taking many. Johnson took a total of 14 shots in the four games leading up to Friday. He took 13 against the Hawks, hitting seven of them.

The four assists and three blocks were each two less than his season totals, and his three steals matched his season total.

"You could see it in our shootaround: he was going 100 miles an hour in our 4:15 shootaround, so you could tell that he was really locked in and engaged," Brad Stevens said.

Perhaps some credit needs to be given to musical artists Future and Drake, the latter of which is a big Raptors fan, Johnson's former team. Johnson said he had rookie Terry Rozier bring a boom box in to the locker room "to get everybody's vibe going and everybody's energy up" because the team arrives to the arena hours before the game.

It worked.

“He brought energy from the jump," Isaiah Thomas said. "We need that from him. He was a big factor in our win tonight. That’s what he does, though. He brings energy. He gets rebounds. He rolls to the basket. He does a lot for us offensively and defensively. We just need him to stay at that level.”

Johnson was able to stay closer to that level in Toronto because he was used to the system there. But coming to Boston over the offseason, he's now adjusting, which can be challenging at first.

"It is, because you have your mindset just playing how we've been playing for six years," Johnson said. "That Raptors defense. Just to kind of transfer that and get the hang of it, it's going to take time but it's coming. It's not going to happen in one day but it's definitely coming along."

Johnson, who now starts for Boston after beginning the season on the bench, was also in the game for the final eight minutes of the fourth quarter. That includes the final three minutes in which the Hawks didn't score again as the Celtics went on a 10-0 run to end the game.

"I told him tonight that’s the best defensive game I’ve seen him play," Jae Crowder said. "It helps me play even more aggressive on the perimeter and Marcus [Smart] and Avery [Bradley]. It helps us, knowing we have a back end like that who rotates if our guy beats us. It helps a lot. It helps our whole team defense and I told him great job on his part tonight."