Celtics’ lack of killer instinct lost them Game 1 — and could cost them series vs. Heat

The Boston Celtics have developed a nasty habit of playing with their food. They better be careful, because they’re up against a guy in the Eastern Conference finals who will swipe it right off their plate.

This isn’t the Atlanta Hawks. This isn’t the choking Philadelphia 76ers. This is Jimmy Butler and the Miami Heat, and they are on the hunt for any weakness in this postseason. Ever since these playoffs began, the Celtics have given off that very scent.

And now, after Miami’s 123-116 win in Game 1, Boston is back in crisis mode — which seems to be the only place from which the Celtics can summon their best basketball.

At some point, though, a team as generous to its opponents as Boston runs up against a series and an opponent that doesn’t reciprocate. With the Heat scoring 46 points in the third quarter, Butler torching the Celtics for a ruthless 35 and Miami making 16-of-31 threes, the margin for error in this series is already gone.

Just like that.

We know by now that the Heat, while technically the No. 8 seed in these playoffs, were not a No. 8 quality team. The Celtics, after battling this team through seven games in last year’s East finals, surely did not take them as such.

But putting forth a full 48-minute effort that matches their immense talent seems to be beyond the capability of this Celtics team. Their good 10-minute stretches are multiple levels better than anyone else in the NBA can muster. Then, when they’re right on the verge of a knockout punch, they exhale and everything tends to break.

Jaylen Brown (7), Jayson Tatum (0) and Malcolm Brogdon (13) walk off the court after the Celtics lost Game 1 to the Heat.

Not that 12 points is a huge lead in an NBA game, but the way the Celtics were locked in offensively and getting to the paint at will in the second quarter, this was an opportunity to show the rest of the league that they were in complete control and ready to take it up a notch after a grinding series against the 76ers.

Instead, the Celtics got casual. They stood and watched as Miami’s intensity put them to shame. As the Heat erased its deficit in a blink with a 46-25 third quarter, the Celtics once again became the team that’s hard to trust.

From there, it was a parade of missed free throws, sticky offensive possessions and weird turnovers — including three from Tatum late in the game when the Celtics still had chances to rescue a victory.

In other words, it was the same kind of messing around that lost them Game 5 at home against Atlanta with an opportunity to finish off the series and lost them Games 1 and 5 against Philadelphia before Tatum’s heroics saved them from an epic meltdown.

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The only good news is that Boston has been here before. The Celtics are an unheard of 10-10 at home over the last two postseasons, which is a testament both to how good they are but also how oddly wasteful they are. True championship teams are supposed to take of their business with a little bit more efficiency.

That, however, doesn’t seem to be Boston’s identity with Tatum and Jaylen Brown, who are obviously spectacular basketball players but have not quite developed the characteristic to finish the job as soon as they can.

The Celtics are the most talented team in the playoffs, bar none. But living that dangerously against the wrong opponent could absolutely derail them before they have the chance to lift the Larry O’Brien Trophy. The way Miami has performed over the last month suggests it doesn’t need much of an opening to kick the whole door down.

Butler has been a missile on the offensive end, but it’s not just him. At age 37, Kyle Lowry’s playoff muscle memory kicks in for just enough stretches to make him really effective. Bam Adebayo is playing with force and pushing pace. There were a couple key possessions in the fourth quarter when Max Strus of all people just locked up Tatum out on the perimeter. And do you even remember the last time Caleb Martin missed a corner three?

Yes, that is the so-called “Heat Culture.” But this series will ultimately be a test of Boston’s culture, which has been defined in these playoffs by pulling themselves out of lethargy and summoning their best only when they have to have it.

That was just barely good enough against the Hawks, and it nearly got them eliminated last week when the 76ers fell apart in the final five minutes of Game 6. Now they’re going to have to do it again. Against Butler and the Heat, they better not wait much longer.

This article originally appeared on USA TODAY: Celtics show lack of killer instinct in loss to Jimmy Butler and Heat