This probably should have been old hat for Al Horford. After all, he’s got 11 seasons of playoff experience and totaled 115 postseason games, or more than double that of ring-winning teammate Kyrie Irving.

And, yet, as Horford lounged on the scorer’s table inside BankersLife Fieldhouse, conducting a postgame radio interview after Sunday’s Game 4 triumph that completed Boston’s first-round sweep of the Pacers, he seemed to be savoring the moment. 

Behind him, Horford's family, including his father, Tito, who has been glued to Horford’s side in the infancy of this playoff journey, reveled with a “Believe in Boston” banner waving nearby.

Inside the Celtics’ locker room, after his typical postgame ice bath, Horford admitted this four-game sweep was particularly satisfying. Maybe it was the roller coaster nature of Boston’s maddening regular season. Maybe it’s all the work that has gone into simply keeping Horford upright, particularly with the knee soreness that has lingered for much of the season. Maybe it was the bad memories of losing to the Pacers twice in the first round of the playoffs during Horford’s time with the Atlanta Hawks.

Or maybe, nearing his 33rd birthday, Horford has simply learned to savor this all a bit more.

Not that age is slowing him down much. Yes, Horford endured one of the worst shooting performances of his career on Sunday, missing 15 of the 19 shots he hoisted. And, yet, in typical Horford fashion, he was still one of Boston’s most impactful players.


That’s the way it was all series. Horford shot 34 percent against the Pacers in Round 1 but you can make the case that he was the series MVP. Heck, his late-game swat of Bojan Bogdanovic in Game 2 might have singlehandedly prevented a loss, kept the momentum on Boston’s side, and allowed the Celtics to trek to Indiana oozing a confidence that helped the team make such short work of the Pacers.

The advanced numbers confirm Horford’s Round 1 impact. The Celtics owned a team-best net rating of plus-15.9 in the 138 minutes that Horford was on the floor, pairing a robust 109.7 offensive rating with an absurd 93.8 defensive rating.

But it’s the off-court numbers that scream his importance. In the 54 minutes that Horford was on the bench, Boston owned a net rating of minus-16.6. The team's offensive rating plummeted to 77.3 in that span. No other player’s off-court rating was even close (next lowest: Gordon Hayward, minus-4.3).

In easier to digest numbers, the Celtics outscored the Pacers by a team-best 46 points with Horford on the court, and were outscored by a team-high 16 without him.

It’s not necessarily surprising that Horford’s play floated quietly below the radar. It always does. And while everyone from Irving to Jaylen Brown to Terry Rozier deserved the attention for their efforts in Round 1, it’s telling that Horford can have an uncharacteristically inefficient offensive series and still have the biggest impact.

Here’s what shouldn’t float under the radar: Horford might just be the most important player when the Celtics and Bucks clash in the Eastern Conference semifinals.

It seems likely that the Celtics will lean heavy on small-ball lineups against the Bucks, this after featuring two-big lineups with Aron Baynes throughout the Pacers series. By going small, the Celtics can try to exploit situations when Brook Lopez is matched up with Horford, forcing him out towards the 3-point line if the Celtics fire away like they typically have against Milwaukee.

Horford played only 69 minutes over two games against the Bucks this season but his on/off splits looked an awful lot like his first-round playoff numbers. The Celtics were plus-16.8 with Horford on the court (110.1 offensive, 93.3 defensive), but owned a net rating of minus-19.9 in three games and 75 total minutes without him.

The Bucks’ offense gets a jolt with Lopez on the court, giving them a 3-point threat and helping space the floor for Giannis Antetokounmpo. Milwaukee’s offensive rating dipped 8 points to a team-worst 106.2 when Lopez wasn’t on the court this season. But the Celtics can force the issue a bit by knocking down perimeter shots.

Going small would also mean that Horford will be forced to match up often with Antetokounmpo, who deserves the MVP for his two-way efforts on a team that was the NBA’s best over the course of 82 regular-season games. While Boston’s success will be dictated in large part by the team’s ability to contain Milwaukee’s role players, it will still be important to make Antetokounmpo work for his points (and avoid the supernova efforts in which he can singlehandedly will his team to victory).


The Celtics could then bring Baynes off the bench to limit Horford’s grind and this might be a series where Semi Ojeleye can add another stout body to throw at Antetokounmpo, something Stevens has done often in the past.

According to the NBA’s tracking data, Horford defended Antetokounmpo on 41 possessions over two regular-season games this season. The Greek Freak was 7-of-14 shooting for 16 points but Horford did a solid job keeping him off the free-throw line. The numbers weren’t particularly glossy for any of Boston’s defenders against Giannis. Ojeleye got 40 turns, allowing 19 points on 7-of-10 shooting with three shooting fouls. It’s notable that Marcus Smart might have enjoyed the most success (7 points on 2-of-6 shooting on 21 possessions). Boston will lean on its stable of switchy forward, particularly Jayson Tatum, Gordon Hayward, and Marcus Morris, and hope to take away the easy stuff for Antetokounmpo (which means tightening up their turnover woes from Round 1, too).

But the brunt of the load will fall on Horford. If his importance isn’t always obvious, it’ll be on the full display in this series. And the Celtics desperately need another dose of Playoff Al if they are to maintain their momentum from Round 1.

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