Boston’s perimeter defense lapses proving costly

The Boston Celtics have lost a little of the head of steam that powered their early-season 10-game win streak to poor perimeter defense — but what will it take to fix it?

You may have noticed the Boston Celtics haven’t been so great at defending the perimeter lately.

And for good reason — the Celtics are allowing the fourth-most shots from beyond the arc in the league, according to Cleaning the Glass. It’s cost the team dearly in winnable games against the Sacramento Kings, Brooklyn Nets, and Denver Nuggets.

It will cost them more if they don’t respond.

“If we’re not going to be a really good perimeter defensive team,” head coach Brad Stevens said (via MassLive’s Tom Westerholm), “we’re probably going to be in trouble, because we’re smaller.”

Boston has been thriving without a traditional, defensive-minded big like Al Horford or Aron Baynes when they move as if connected by one mind, but that high-level switching defense has sputtered a bit of late, and sometimes to disastrous effect.

In the midst of one of the most impressive defensive seasons put together in recent years, guard Marcus Smart is taking to heart. “We have to make them miss.” Smart said.

“It starts with me. I played like [expletive] today, and the night before. We got lucky the night before. Today, it burned us. It starts with me. I have to do a better job of getting my team ready, and setting the tone on both ends of the court. I just have to contest more. That’s it.”

One could hardly blame the early-season Defensive Player of the Year candidate for the lapses, but it’s the sort of leadership the team will need to tamp down on the trey party that has been Boston’s defense of late.

With All-Star wing Gordon Hayward closer to a return than not, help is most definitely on the way. And Smart himself is pretty banged-up as a result of his smothering style of defense.

But, it will take more than reintegrating the Butler product and a stretch of days off for the Texan to elevate the Celtics defense to where it needs to be to hold off a modern NBA team.

To Smart, the aches and bruises are no excuse.

“I can’t really worry about it too much. I can’t let it stop how I play on both ends. If I’m out there I have to be able to produce and play. Otherwise I have to sit my ass down.”

And while sitting a game or too against weaker opponents is probably not a terrible plan for the Oklahoma State product, it’s also not the only approach on the table to boosting the D, nor should it be.

Relaxing on two-pointers by itself isn’t a viable approach according to head coach Brad Stevens, at least against the Nets. “[Y]ou don’t want to accept dunks.”

“Dunks and layups are the killers, and they do a good job of not shooting too many bad ones … When we overreacted on close-outs, they got to the rim or Allen dunked it on us, Jordan too.”

Could the answer be as simple as being the team on the floor with the most effort? UConn product Kemba Walker thinks that’s a factor in what powered Brooklyn to their win Friday:

“These kind of games are all about the teams who want it the most,” Walker explained. “That’s what it was. They wanted it more than us, especially after us getting them at home, where they played well — we just got over the hump and won that one. But tonight you could tell they wanted it, and they came out and got that win.”

For the Celtics to succeed against even the league’s middle-of-the-pack teams without a defensive stopper in the lane, they’ll need to bring a stronger, more cohesive effort to the fore each night they step on the court.

Recent losses have been as much about effort — especially early — setting the tone for the rest of the game, and resting on the team’s past success will only lead to failure, a lesson (hopefully) learned all too well last season.

However, we have seen a unity of purpose shared by this team to be a real phenomenon likely coming back down to earth a bit. The wear and tear of an 82-game season makes putting such an intense brand of basketball on display every night of the season a daunting, perhaps near-impossible task.

It doesn’t mean the team necessarily needs a trade, nor that it will continue.

But Boston will need to tighten up to continue exceeding our initial expectations.