Robb: Celtics Achilles' heel ends their season in Game 6

The Celtics found a way to beat the Heat in Game 5 by eliminating their biggest problem in the series: crunch time. Blowing out the Heat in the third quarter ensured there would be no tight game to worry about late as they sustained the momentum and double-digit advantage. The same was true about the C’s other win this series (Boston lead by 16 with five minutes left against Miami in Game 2).

Boston’s Achilles heel emerged yet again in Game 6, though, just as the Celtics were nine minutes away from forcing a Game 7 against the Miami Heat, holding a six-point lead after opening the fourth quarter with a 10-2 run. In order to get past the Heat, the C’s would need to put their crunch time demons behind them and execute late.

Instead, the Celtics saved their worst late-game play of the year for Sunday night, watching as their season was taken from them with a 26-6 run by the Heat over the next six minutes of play. When the dust cleared, the Celtics were facing their first double-digit loss of the postseason and first as a team since February 11th (34 games). Miami shot 56 percent from the field and 48 percent from 3-point range, both playoff-highs for a C’s opponent as they posted a postseason-high 125 points in regulation.

After the game, Brad Stevens heaped praise on the Heat for dominating the crunch time play.

“Miami deserves a lot of credit,” Stevens said. “They’re super physical, super tough, very, very savvy. And I think they’re the best team in the East and deserve to be representing the East the way that they’ve played.”

However, amid a fourth quarter in which the Celtics failed to get a stop on 10 consecutive Heat possessions at one point, it was jarring to see a top-5 defensive team in Boston put together a bottom-three outing for the season on that side of the floor. The late struggles began in the Toronto series (Game 3 and Game 6 late blown leads, a near collapse in Game 7) but rose to a different level in the 4-2 loss to the Heat.

The Celtics were outscored by 28(!) points in 19 crunch time minutes during the series spread across five games. Here's a statistical breakdown of those woes for Boston offensively in those 19 minutes:

31 percent shooting (9/29)
7 percent from 3-point range (1/13)
6 turnovers

That ugly perimeter shooting was the story of Boston’s fourth-quarter offense in Game 6. After drilling 11 3s in the first half, the C’s went 4-of-23 in the second half from beyond the arc. They missed some good midrange looks early in the fourth quarter but quickly devolved into early shot clock 3-point heaves to try to match Miami’s hot scoring in the fourth-quarter run. Good ball movement largely vanished as the C’s fell into the temptation of 3s against Miami’s 2-3 zone was too much. It was a gamble that paid off for Miami as the C’s went cold late.

“I don’t think we were pressing,” Kemba Walker said of Boston’s late shots. “I thought we got some really good looks. Just, they didn’t drop. Whenever we did miss, those guys they brought it back with great pace and made the plays and that started it up. That was the big difference. They made the plays and we didn’t.”

The bigger story of the game for Boston late though came on the defensive end. The Heat scored 26 points in a six-plus minute stretch in the fourth quarter to win the game, including the aforementioned 10 straight scores that turned things from tight to a blowout in the final two minutes of the series-clinching win for Miami.

Once again, it was the same story for a Heat team that was able to put up points when it mattered. Here’s a look at how well Miami’s offense executed in crunch time over just 19 minutes, posting a whopping 1.5 points per possession:

17/29 FG
7/15 3PT
16/18 FT

The only time all night when the Celtics got some defensive momentum going was when Grant Williams spent some time at center midway through the second half, which led to a 20-6 Boston run and the lead (the fact that it took so long for Stevens to get to Williams is worth wondering). Beyond that strong stretch? Miami had their way with the C’s all night, scoring 125 points per 100 possessions, easily the best offensive performance the C’s have allowed in the bubble. Paul Pierce called the C’s out at halftime on the ABC broadcast for a lack of urgency on the defensive end and that proved to be right.

Still, a positive mentality carried out of the C’s locker room after the disappointing loss.

“We gotta grow,” Walker said. “We’re going to have to figure out how to win those games down the stretch. But we got time. We’re about to be outta here, but at some point, we’re going to look back at this and just learn. It’s all learning experiences. We all just have to have big offseasons and be ready to come back whenever we start back up.”

That mentality feels a bit foolish however when taking a closer look at the guys who beat Boston when it mattered. The Celtics have far more playoff experience on the floor in crunch time than the Heat among their biggest contributors. Bam Adebayo and Tyler Herro were the game-changers during the Heat’s 26-6 run with Adebayo punishing the C’s off the dribble late (career-high 32 points) and Herro (11 fourth-quarter points) beating Smart with great 1-on-1 moves on multiple occasions. Those guys ended up being better than Tatum, Walker and Brown when things mattered and that ultimately was the series.

The Celtics head home now despite finishing the series with a positive point differential that wasn’t enough to overcome a -64.7 defensive rating in crunch time. Yet there remains optimism in the wake of those struggles.

“I think we played hard,” Jaylen Brown said. “Obviously we feel like we underachieved, but still no reason to hang our head. I think we’ve got a really good group, a young group, a talented group that’s only going to do nothing but improve. Once again, it stings, but I’m still very very proud of this group.”

Improvement should come again as Brown and Tatum enter their primes but other issues must be addressed this offseason. Smart (22 shot attempts in Game 6) must be reeled in with his shot selection. Danny Ainge must get more aggressive in adding win-now pieces to his bench instead of piling up rookie contracts that may or may not pan out, which left this team in a bind after Gordon Hayward’s injury and slow recovery (he was far from 100 percent) for a series like this. Brad Stevens needs to closely examine this team’s crunch time woes (4-8 in games decided by less than three points since February) in this series and season for his inability to settle down the troops in tough spots until most of the damage was done.

For now, it’s clear. These Celtics weren’t ready yet to seize the moment and they can only hope now they get another chance against a stacked Eastern Conference in years to come.