Al Horford, right, turned down a $30.1 million option to remain with the Celtics in the offseason and signed with the Philadelphia 76ers. Kim Klement/Pool Photo via the Associated Press

There was a whirlwind of happenings that unfolded when NBA free agency opened in the summer of 2019.

Kyrie Irving left the Celtics for the Brooklyn Nets, while Kemba Walker signed a free-agent contract to replace him, with Terry Rozier moving into Walker’s spot with the Charlotte Hornets.

And in the middle of all that, Al Horford declined his $30.1 million option with the Celtics and departed for the Philadelphia 76ers in a surprise move.

Just over a year later, Horford and the Celtics will be renewing acquaintances in the opening round of the playoffs at Disney World, starting with Game 1 on Monday night.

Horford, who signed a four-year, $113 million deal with the Celtics in 2016, went to the Sixers via a four-year, $109 million contract, with $97 million guaranteed.

After helping the Celtics play in the Eastern Conference finals in 2017 and 2018, Horford will now be trying to eliminate them.


“It’s part of the business,” said Horford on a video conference last week. “Obviously, we’ve already played them plenty of times this year, so that effect is kind of out of the way, so now we can just go out there and compete. It should be a fun series.

“I’m grateful for another year to be in the playoffs and be able to compete and go out and do what we do.”

Horford played 208 games in three seasons with the Celtics, averaging 13.5 points, seven rebounds and 4.6 assists.

He did not make a smooth transition with the 76ers, struggling at times throughout the season. Horford averaged 11.9 points, 6.8 rebounds and four assists as he tried to get comfortable on a team with Joel Embiid and Ben Simmons as the main players.

Horford’s former teammates looked to him as a leader during those three years in Boston.

“Watching Al for the last couple of years was great,” said forward Semi Ojeleye. “We have to be ready. We know he’s a high caliber player. He can hurt you in the post or the outside, so we have to prepare for him.


“He’s a big part of their team, so we have to be aware that he’s going to be involved in a lot of what they’re doing.”

The Celtics tried to retain Horford, even after Walker signed to make it a tight squeeze with the salary cap, but he decided to depart following a chaotic season in Boston.

“It wasn’t an easy decision,” said Horford last summer. “I felt like there was going to be a lot of options for me. When June 30 came around, things escalated very, very quickly. There were multiple teams, a lot of strong interest, and I had to make the best decision for me.

“I was very surprised there was that strong interest for me being here. It made the decision very easy.”

THE CELTICS WILL likely have three first-round picks in the NBA Draft, which takes place on Oct. 16.

Because the Memphis Grizzlies missed the playoffs, the Celtics will get the Grizzlies’ pick if it remains at No. 14 during the draft lottery on Thursday night.

The pick, which went to the Celtics in the Jeff Green trade in 2015, will be retained by the Grizzlies if they move up into the top four in the lottery. The Grizzlies have just a 2.3 percent chance of having that happen.

As a result of finishing with the fifth-best record (48-24), the Celtics’ own choice will be No. 26. They also own the No. 30 pick from the Milwaukee Bucks via the trade that sent Aron Baynes to the Phoenix Suns last summer.

Comments are not available on this story.