Seven seasons, 465 regular season games, 119 playoff games, five Eastern Conference Finals appearances, two NBA Finals appearances, and an NBA title. For most NBA franchises, this would be more than enough to have your number raised to the rafters… but the Boston Celtics are unique as the most decorated team in NBA history.
Now that Al Horford has said farewell to the Celtics, we can look back on his time in green and weigh whether or not he deserves to have number 42 retired forever. To better evaluate his case for joining the Celtics’ greatest legends, we must look back at his influence on the franchise and his impact on the court as a Celtic.
This footprint, both on and off the court, must be elite. Only two players have had their number retired by the Celtics in the last 20 years. The first was Paul Pierce, Finals MVP and second all-time in points. The second, Kevin Garnett, Defensive Player of the Year, the soul, the heart, and the pedestal that led the Celtics to the 2008 title.
So, did Al Horford reach that elite level of performance? Well, let’s dive into the past!
Looking back at Al Horford’s career as a Celtic, the first word that comes to mind is “winner.” In green, Horford won 69% of his games, peaking at 79% in the 2023-24 season. For comparison, Kevin Garnett — the latest Celtic to have his number retired — had a 67% winning rate. While Horford didn’t win games alone, this speaks highly of one of his biggest strengths: adaptability.
The Dominican star first paired with Isaiah Thomas in a devastating two-man game that helped unlock Thomas’ offensive superpower during the 2016-17 season. For that stretch, the Celtics’ overall level was far better when Horford was there to be the needed lieutenant. With Horford and Thomas on the court together, the Celtics had a +3.9 net rating. When Horford sat and IT played without him, the net rating dropped to +0.9.
Following the Isaiah Thomas era came the Kyrie Irving era — and Horford still delivered. Those two years had their ups and downs, but Horford consistently elevated the team. When Kyrie got injured and Gordon Hayward was still finding his rhythm, Horford led a young Celtics team all the way to Game 7 of the Eastern Conference Finals. Against Giannis Antetokounmpo, then Joel Embiid, Horford anchored the defense and served as a facilitator for a group of young players ready to step up.
Again, his impact was clear: a +6.88 net rating with him on the court, compared to +0.93 without him. This tendency to always have a positive effect on competitive teams has been true throughout his career. He only missed the playoffs twice — once in Atlanta, and once in OKC during a tanking season. Back in college, Horford even won back-to-back (!!) titles with the Florida Gators. A certified winner.
And if we look at the more recent stretch from 2021 to 2025 — once Brad Stevens brought him back to Boston — Horford still had a very positive impact on a stacked roster: +9 net rating with him on the court. Elite numbers, leading to two NBA Finals and one NBA title. That 2024 championship might be what makes Horford’s case so strong for having his number retired in Boston.
Horford understood perfectly what it meant to be part of this tradition. He did everything he could to achieve what might be the biggest challenge in basketball: winning as a Celtic. As he said, “You can win championships in many places, but there’s nothing like winning in Boston.”
The 2024 playoff run encapsulated that perfectly. After a regular season spent coming off the bench, he rose to the occasion in the playoffs, averaging more than 30 minutes per game and starting 15 of the 19 contests.
Al embodied the Ubuntu mentality that carried the Celtics to their 2008 title. “I am because you are.” This philosophy embraces the idea that humans cannot exist in isolation — and Horford’s Celtics career was the perfect example. He became whatever was needed, adapting to whichever environment was built around him.
His ability to provide what was missing, on any type of team — from average rosters to all-time stacked squads — made him invaluable. It also explains why he never collected many individual accolades. You don’t earn All-NBA or multiple All-Star selections by fitting seamlessly everywhere, and maybe that’s why he won’t be remembered quite like other Celtics stars.
Nonetheless, when you look back at his impact and longevity, Horford deserves a lot of credit.
Among the brightest stars
Another criterion beyond winning is longevity and placement in all-time rankings. It’s worth what it’s worth — sometimes overrated — but people love records and all-time lists. So where does Horford stand among Celtics history?
His rankings are quite revealing and highlight how modern his game truly is. He’s top 10 in total rebounds and rebounds per game. Same for blocks, ranking sixth all-time for the Celtics. But he’s also in the top 10 for 3-pointers made and attempted — and among the most efficient players, ranking top 10 in eFG% and 2-point FG%.
For a player who started his career as an undersized big who didn’t shoot threes, this shows just how adaptable Horford is. Rankings alone aren’t always the best way to evaluate a player because eras and contexts are so different. Still, his presence across so many categories for one of the NBA’s oldest franchises perfectly illustrates his uniqueness as both a player and a Celtic.
Looking beyond the basketball court, Horford’s leadership was undeniable. Jayson Tatum, who grew into the Celtics’ go-to guy and led them to a title, said, “Al showed me what it means to be a professional.” Horford set a high standard and made sure younger players followed his example.
Even his decision to sign with the Celtics back in 2016 was groundbreaking. As detailed in HBO’s recent series on the Boston Celtics, Horford was the first Black free agent to choose Boston. While that might seem anecdotal to some, it underscores just how historic Horford’s presence was — both on and off the court.
Would it be enough to retire #42 forever?
The case looks strong. Horford impacted both the Celtics and the city of Boston. He helped deliver the 18th title, maybe one of the most important in franchise history. He performed at the highest level, and the Celtics were always competitive with him in the lineup. He adapted to every situation and ensured the stars could shine because of him.
And yet, perhaps this very adaptability explains why his case isn’t ironclad. Looking up at the rafters, the retired numbers belong to players who were the face of the team — the leaders carrying Boston to the summit — not necessarily those who fit around the stars.
Players whose numbers hang in the TD Garden are those without whom nothing would have been possible. Does Al Horford fit that category? Looking back at everything we’ve just explored, I believe he does. Yes, he was never the offensive leader, the primary playmaker, or the constant difference-maker. But he was the foundation of the elite defenses in 2018 and 2022. He was there when Porzingis went down during the 2024 Finals run. He gave the Celtics a chance in 2017 through his synergy with Isaiah Thomas. He led a young group to the Eastern Conference Finals in 2018.
So no, Al Horford was never the Celtics’ franchise player. But he was their godfather. And that is why his number belongs in the rafters.
