The Boston Celtics had a golden opportunity on Friday night. They had a real chance to make up ground on the Cleveland Cavaliers for the top seed in the Eastern Conference.

Instead, they blew a 25-3 lead and let the Cavs have the biggest comeback victory in the NBA this season. Now, they sit 7.5 games behind the Cavs for the number-one spot.

They ended up losing this game because the Cavs were able to expose their biggest weakness. Even though they are the second-best team in the East, this is still a big flaw in their roster.

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The Cavs were able to come back from their huge deficit because they decided not to have two bigs out on the floor in the fourth quarter. They had Evan Mobley as the sole big man.

In the final four minutes, they had neither Mobley nor Jarrett Allen on the court. They just used their speed and hustle to close the game.

Despite Jayson Tatum and Jaylen Brown doing their best to keep this game in Boston’s favor, they weren’t able to deal with the no-big lineup.

That could be a lineup that the Cavs deploy in the playoffs against the Celtics. It has clearly become their biggest weakness.

Sam Hauser got abused on switches in this game, too. Their bench doesn’t have enough defensive depth to play some of the best teams in the NBA.

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It didn’t help that they were without Kristaps Porzingis for this game, so they didn’t have their best big. It’s clear that he has to be healthy if they want to beat the Cavs in the playoffs.

Al Horford just can’t carry the load as the sole big man in the lineup anymore. Had they had Porzingis available for this game, perhaps they would have been able to close out the victory.

Regardless of whether or not he’s out there, the Celtics have to figure out a solution to this problem. It’s the one thing that can slow them down once the playoffs get here.

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