Al Horford: 3-point specialist.

Can you imagine that description of the center when he was drafted by the Hawks with the No. 3 overall pick in 2007?

Sixteen NBA seasons later, now a member of the Celtics for the second time, Horford has evolved his game and continues to play meaningful basketball. The transformation started in Atlanta.

“I think it all started here for me, even the 3′s, because Coach Bud (Mike Budenholzer) was always encouraging me to shoot them,” Horford told The Atlanta Journal-Constitution on Thursday before Game 6 of the Eastern Conference playoff series against the Hawks. “At first, I was probably getting a lot of looks and what is he doing and things like that. But that coaching staff that was here my last few years really believed in me and really encouraged me. That’s where it really started for me. I feel like that’s been part of the reason I’ve been able to extend my career and play meaningful basketball at this point in my career.”

The 36-year-old Horford took 479 shots this regular season, making 47.6%. Of those, 325 where from 3-point range, where he shot 44.6%. That means more than two-thirds of Horford’s shots this season were from beyond the arc.

In the first five games in this series, Horford is 9-of-24 from the field, including 7-of-19 from 3-point range.

That Horford helps stretch the court as a legitimate 3-point threat is a major part of the Celtics offense. Horford averaged 6.4 points and 6.2 rebounds during the regular season. He is averaging 5.0 points and 6.8 rebounds in this series.

“His shooting allows great isolation players like Jayson (Tatum) and Jalen (Brown) room to operate, the whole offense really,” said teammate Mike Muscala, who also played with Horford in Atlanta. “Credit to him for putting the work in and expanding his range.”

It’s not only about the points and rebounds for Horford. Never has been.

Consider his stat line for two games in this series:

In Game 5, the dramatic 119-117 Hawks win in Boston, Horford became the second player in Celtics history to record at least five rebounds, five assists and five blocks in a playoff game, joining Paul Pierce in 2005, and becoming the 34th player in NBA history to post such a stat line.

In Game 4, a 129-121 Celtics win in Atlanta, Horford had 11 rebounds, five assists, two steals, and zero points (on two attempts), becoming one of only two Celtics to register zero points and 10-plus rebounds in a playoff game, with Kendrick Perkins in 2010.

Horford plays winning basketball. He helped the Celtics to the NBA Finals last season. He has reinvented himself to keep up with the changing NBA. Former Celtics coach Brad Stevens, now the team’s president of basketball operations, picked up where Budenholzer and company left off by encouraging Horford to spread the floor, even though Horford had one of the top mid-range games in the league. He won’t be confused with former Hawks teammate Kyle Korver, but Horford’s range helps make the Celtics go.

Horford said it was during the 2018-19 season, the last of his first stint with the Celtics, that shooting 3-pointers became routine.

“That’s when I realized it was OK to shoot them. You feel good about it; you don’t think about it as much,” Horford said. “Now, most of my shots, that’s what I do. The way that the game is changing, I’m such a competitor, I’m trying to do whatever it takes and find a way to be relevant and having an impact on the game.”

Horford played nine seasons in Atlanta and was a four-time All-Star. He signed with the Celtics as a free agent and played three seasons. He rejoined the Celtics two seasons ago after one-season stints with the 76ers and Thunder. After a trade from the Thunder for a second stint with the Celtics, Horford signed a two-year, $20 million extension. He is signed through the 2024-25 season.

The Hawks, after a lengthy playoff absence, made the playoffs in all nine of Horford’s seasons in Atlanta. Most in the league don’t consider that a coincidence.

As Horford returns to Atlanta, in a tightly contested playoff series, he understands the circumstances. He is a Celtic. Still, this city still feels like home in many ways. He has family here. He grew up as a player and a person here. He still credits so many connected with the organization with where he is today.

“It was great time for me,” Horford said of his reflections of the time with the Hawks. “I couldn’t ask for more from being drafted and being in a better position than I was here. From the GM who drafted me, Billy Knight, coach (Mike) Woodson, and throughout the years all the people who impacted me here and helped shape me to the type of guy I am today, is because of this organization. I’m very grateful for all my years here.”