How Al Horford, a 38-year-old backup center, is key to Celtics’ NBA Finals success

DALLAS – He’s not their best player. He didn’t even start most of the season. And he’s only averaging 7.7 points per game through three games of the NBA Finals.

And yet, as the Boston Celtics close in on the first championship of the Jayson Tatum–Jaylen Brown era, it’s amazing how essential a 38-year-old center is to the entire thing.

Al Horford isn’t the first name that rolls off your tongue when you mention these Celtics. Tatum and Brown are the Celtics’ two best players, and one of them is going to win finals MVP. (At least, if Billy King doesn’t.) And if we’re arguing about who the best players on the Celtics are, that discussion has to include former All-Stars Jrue Holiday and Kristaps Porziņģis and All-Defense mainstay Derrick White as well.

Nonetheless, Horford might be a more essential piece than all of them, especially if the injured Porziņģis can’t return. Remove Horford, too, and Boston’s entire switching, stretching, Jenga architecture collapses.

That was never made clearer than in these playoffs, when Porziņģis’ absence in 11 of 17 games entering Friday forced Horford into the starting lineup, with multiple Boston blowouts along the way.

Horford has averaged 30.6 minutes per game in the postseason — quite an upgrade from the career-low 26.8 he played in the regular season and more than he’s played in any regular season since his last All-Star campaign in 2017-18. That number jumped to 37 in Game 3 against the Mavericks with Porziņģis out of the lineup again, more than the 35 he averaged in the conference finals against Indiana. Included in that series were two 40-minute efforts, the most he’s played since a double-overtime game against New York in March 2023.

It’s not just that Horford is playing these minutes, but also that he’s lending a rare combination of skills that enables Boston’s entire perimeter quartet to be more than the sum of its parts. Horford is a knockdown 3-point shooter essential to Boston’s five-out spacing that has run Dallas ragged in the finals … and also a switchable big who, even at this advanced stage of his career, can tap dance with elite guards on the perimeter and hold his own. He makes less than the midlevel exception, and yet, how many bigs in the league can do both these things at his level?

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It is, in many ways, a full-circle journey for Horford. Coincidentally, he started his playoff career playing against Boston’s last championship team in 2008, as a rookie with the Atlanta Hawks. Those Hawks surprisingly took Boston to seven games in the first round (Game 7! ), but Horford wouldn’t taste an NBA Finals game for another 14 years.

Back then, he got his baskets on offensive rebounds and left-block post-ups, turning and shaking the ball across his waist three times before either going up for a short jumper or driving for a right-handed hook shot. Horford didn’t make a single 3-pointer his rookie year or the next one. He didn’t shoot 3s with any volume until 2015-16, when he had already been in the league for eight years and made three All-Star teams.

Fast-forward to 2024, and Horford plays an entirely different game. He never posts up (well, almost never); instead, two-thirds of his shots were 3-pointers, as the arrival of head coach Joe Mazzulla accelerated Boston’s transition to a five-out team that strafes opponents from behind the arc.

And if you haven’t noticed, he is absolute cash: Horford made 41.9 percent of his 3s this season and 44.6 percent a year ago.

It’s not just the accuracy, either. The “one one-thousand, two one-thousand” set shot he first began launching in 2015 was good enough if he was pick-and-popping against the dinosaur bigs of yore, but as the game changed, Horford needed to keep evolving. Look at how fast his trigger is on this corner 3 in the first quarter of Game 3. Any slower, and Derrick Jones Jr. spikes it.

Along the way, his evolution is part of a bigger story that has changed basketball. It’s not a giant exaggeration to say Horford, and those Hawks teams, changed the NBA. While they weren’t the first to discover the value of spacing and launching 3s, they were at the leading edge of the trend that saw midrange shooting centers move beyond the arc instead.

Within two years of Horford’s 3-point emergence, guys such as Brook Lopez and Marc Gasol were flinging away from behind the arc, too, and the Clifford Robinson Memorial Long 2 from the top of the key went the way of the dodo.

(Horford, incidentally, played a minor role in a seminal moment along that way — perhaps the most important moment in NBA history that nobody watched — when his absence in the 2014 first-round series against top seed Indiana forced the eighth-seeded Hawks into a David vs. Goliath strategy of having Paul Millsap, Mike Scott and Pero Antic bomb away on pick-and-pop 3s against Pacers rim protector Roy Hibbert. Atlanta took 230 3s in seven games — a preposterous total in 2014— and it worked so well that the Hawks nearly won the series. It also offered every other team a cheat code for dealing with Hibbert; the runner-up for Defensive Player of the Year in 2014, he was out of the league within three years.)

That wholesale transition at the offensive end, however, is only the second most impressive thing about the Horford Experience.

Defensively, he shouldn’t be doing this. He’s 38, and Boston’s entire defense is based on switchability, which means he’s often chasing around the likes of Luka Dončić and Kyrie Irving, or in previous rounds, stars like Tyrese Haliburton and Donovan Mitchell.

Amazingly, Horford has kept up. I can’t emphasize enough how cruel the playoffs are when it comes to probing and exposing any weakness a team has. Mavs fans are experiencing this now, with one bench player after another getting exposed as Jason Kidd keeps toggling to his next option hoping for a solution. Horford defending on an island against Dončić and Irving should be a classic example of the playoff crucible being too hot for somebody.

And yet, against two of the best offensive players in the league, the 38-year-old Horford hasn’t been exposed at all. His defensive plays have been some of the standout moments of the series, such as this incredible hustle to book it out of the corner in Game 2, chasing down Dončić and Dereck Lively II to take way a Dallas fast break.

Are we sure this guy is 38?

More often, what stands out on the rewatch of the tape is the extent to which he uses his basketball IQ to overcome whatever physical deficits a matchup may give him. Horford makes subtle plays like this switch below countless times a game.

My favorite little thing this half is the switch Horford and White execute after White bites on Kyrie’s pump fake pic.twitter.com/iEPmp2GOMw

— Anchorage Man (@SethPartnow) June 7, 2024

“Al has been the same way since we’ve been in Atlanta,” said Dallas guard Tim Hardaway Jr., who was his teammate with the Hawks in 2015-16 when they won 48 games. ”Always solid, never doing too much, never getting out of sync, keeping everybody together, an anchor on defense (and) talking on defense, which gives the guards amazing confidence knowing he has their back behind them.”

Even as he is challenged by younger, faster players, Horford uses his basketball IQ as the great equalizer. Watch him in this series anytime he guards Dončić in isolation; he takes a stance on Dončić’s left hip and makes sure he won’t be getting a stepback 3 going to his left.

On this play in Game 1, he took away the Dončić stepback to his left with his positioning, then still blocked the stepback going right.

The most unbelievable sequence might have been in the third quarter of Game 3, however, after Horford checked back in for Xavier Tillman. He picked up Dončić on a switch and stuffed him so completely that he couldn’t get a shot off and had to dump off a pass to Irving.

Two seconds later, after a deflected pass, Irving had the ball at the top of the key with a live dribble and Horford on him. After tracing him left and back to his right, Irving settled for a tough pull-up in the lane that clanged harmlessly off the rim.

That’s 20 seconds of dribbling from two All-Stars against Horford, encompassing 11 dribbles and two ineffective passes, and Dallas got bubkes.

That sequence foretold the conclusion of Game 3, on arguably the most important possession. After already playing 36 minutes, Horford chased the much smaller and faster Irving. Knowing his tendencies, he was able to force him to rush into a stepback 3 going right just to get a shot away.

Overall, NBA.com’s tracking data has Dončić and Irving shooting just 8 of 29 on possessions where they are guarded by Horford. Dončić, in particular, has had a much easier time when not going at Horford, especially when he attacks Tatum instead; in a related story, the Mavs have steadily chilled on isoing against Horford and instead sought out other advantages as this series has gone on.

Horford is playing so much in these finals because of an injury to a player nicknamed The Unicorn. In the modern era of spacing and switching, it’s the 38-year-old version of Horford who might be the true unicorn — a knockdown 3-point threat who can score in the paint against switches and move the ball on offense, and a center who can captain the defense and switch across every position, even against All-Star guards.

Seventeen seasons into his career, Horford is one win away from his first championship, and this wasn’t just some brief cameo to get a ring. Others will get the headlines, but his role in Boston’s dominating run has been vital.

Required Reading

(Top photo of Al Horford and P.J. Washington: Stacy Revere / Getty Images)