ATLANTA -- Al Horford knows this won't be just another game tonight.
The four-time All-Star is returning to Philips Arena for the first time with a new team, and many are still adjusting to the fact that he no longer plays for the Atlanta Hawks.
After nine seasons as a franchise cornerstone, Horford left for Boston as a free agent last summer, signing a four-year, $113 million contract.
But a big part of the big center will always be in the Deep South. He hopes his impact with everyone in Atlanta was positive.
"I always tried to be a guy that plays hard and was committed to giving his all, on and off the court," Horford said Friday. "So that's something I'm really proud of."
Horford led Florida to back-to-back national championships before the Hawks drafted him No. 3 overall in 2007. He helped Atlanta make the playoffs each season he was with the franchise, but the team only got close to the NBA Finals once, in 2015. The Hawks won 60 games and advanced to the Eastern Conference finals for the first time.
They were swept by Cleveland each of the last two years, and coach Mike Budenholzer has remade the roster. Kyle Korver now plays for Cleveland, Jeff Teague for Indiana and DeMarre Carroll for Toronto.
The Hawks have rebuilt around Atlanta native Dwight Howard, an eight-time All-Star center, and point guard Dennis Schroder. The overhaul continues to be a work in process with just four players with double-digit scoring averages and the team lacks consistent perimeter shooting.
"It really has changed fast," Horford said. "That just shows us what the NBA business can be like sometimes. That's just the way it is. All you can do is embrace those times that you had here and accept these new challenges that we're in."
In his first game against the Hawks, Horford said he expects some mixed emotions, but hopes to settle down after a pregame video tribute. There's plenty at stake tonight with Boston third and Atlanta fourth in the Eastern Conference. The Celtics have won five of six and the Hawks seven in a row.
Horford keeps up with some of his former teammates and wishes them well.
"It's a team that's gone through its ups and downs, but I feel like they've found a really good rhythm right now," he said. "They're playing really well. Dennis has impressed me a lot, the way that he's been playing and leading the team. Paul (Millsap) being as consistent as he is, and Tim (Hardaway Jr.) is really impressive off the bench."
Horford said many times over the years that he wanted to spend his entire career with the Hawks, but when they wouldn't match Boston's offer, his decision was easy.
"I think for me individually it was the right decision," Horford said. "It takes time to adjust to a new team, a new city and everything, but my teammates and coach have made my transition very easy."
Boston guard Isaiah Thomas credits Horford with helping him get off to the best start of his six-year career. Thomas is averaging 28.2 points, tied for fourth-best in the league. Horford is averaging 15.3 points, 6.9 rebounds and 4.9 assists.
"He helps me out because he puts me in position," Thomas said. "He sets really good screens for me to get me open and he also is a hell of a passer, so when he gets the ball in situations where I'm on the opposite side, he usually finds me. I think that's what making me have a pretty good year as well."
Thomas said the Celtics intend to get Horford a win Friday night.
"He hasn't brought it up to us," Thomas said. "That's just the type of person he is. Everything is the same for him."
Horford likes to keep it that way. He's ready to put this game behind him.
"It's a little different, but I think probably tonight I'm sure it will be more surreal for me," Horford said. "Right now it's just a shoot-around and it feels very normal."