BOSTON — The Celtics entered the season uncertain at the center spot, but Neemias Queta’s breakout season has steadied the ship. Queta has been a force inside the paint and a huge part of the team defensively, but there has been one notable weakness so far.

Queta is shooting just 61.2% of his 2.1 free throw attempts per game. He came into this season shooting 71.3% in his career on free throws, so that’s a big difference. Also of note, he’s only taken 49 total free throws this season, meaning it’s not a massive sample size. Regardless, the big man said he’s looking to up those percentages.

“I can get better,” Queta said. “It’s been a tough year for me at the line. I usually feel pretty confident when I’m out there. I don’t know what’s going on. Maybe it’s repetition or maybe it’s just getting my legs under it. But something I need to get better at, most definitely, because that’s unacceptable. … I’m too good of a shooter to shoot that bad.”

Queta has been an important piece for the Celtics, getting the promotion to starter. The C’s had Kristaps Porzingis, Luke Kornet and Al Horford depart the roster, meaning Queta was the likely projected starter. He’s taken that job and then some as he’s enjoyed a career-best year.

The Celtics have also gone small in recent games when Queta takes a break, putting in guys like Josh Minott at the center spot. They have other backup big men like Luka Garza and Xavier Tillman, but they haven’t made much of an impact in recent weeks. It’s why Queta is such a unique presence on the team as their starting big.

The C’s have been a pleasant surprise to open the season with a 15-10 record, good for third in the East. Queta’s been an important part of the operation, though he’ll look to improve on his free throws.

“I feel like I’m pretty good in my free-throw percentages,” Queta said. “I usually go confident, and a majority of times I make them. I don’t know what’s going on this year. Gotta get right. Watch film. Get repetitions. I’ve been getting right in them. And I think it’s a matter of time before I get going. Maybe it’s just a shooting slump. That’s how I like to see it. I’ll get better at that.”