BOSTON — Fresh off his best performance of the 2018-19 season, Boston Celtics All-Star point guard Kyrie Irving offered praise to a rather unlikely target for helping him get on track: Tommy Heinsohn.

Irving said he took it as a challenge when Heinsohn twice suggested during NBC Sports Boston broadcasts that he felt Irving came into the season out of shape, contributing to his uneven start to the new year.

Irving put up a season-high 31 points on 10-of-16 shooting as the Celtics held off the Detroit Pistons 108-105 on Tuesday night at TD Garden. Irving entered Tuesday’s game shooting 39.1 percent from the field and 24.1 percent beyond the 3-point arc but looked far more like his old self.

Playfully asked in an on-court interview with NBC Sports Boston about whether his new haircut had contributed to his offensive outburst, Irving instead referenced Heinsohn’s recent critiques.

It was hard to tell if Irving had been angered by Heinsohn’s analysis based on his on-court comments but, in the locker room following the game, he expounded.

“It's always great when someone challenges you like that. Especially with the respect level that I have for past Celtics legends,” said Irving. "And for him to really kinda pinpoint as me being one of the leaders on this team, the main [focal] point of this team, I had to be in better shape as well as challenge myself on both ends of the floor. I think he made it very clear to me. 

"I caught wind of it, probably like a week ago. And it was bothering me because it was the most honest thing that anyone had said about the way I was playing because I literally had to try to match a level that I had playing at last year, but also become better. So how do you do that? I had to really put an emphasis on my body and how I’m taking care of my mind. 

"That was one of the realest things that I could have heard. As a competitor, if that doesn't irk you, itch inside you, of you wanting to be better, especially when a guy -- Tommy Heinsohn, you can’t do any wrong in his eyes if you’re a Celtic. You can’t do any wrong. And I appreciate that. And it was the truth.”

Despite spending the summer rehabbing from the two knee procedures that ended his 2017-18 season in March, Irving seemingly arrived to camp in top shape, looking lean and strong in the small glimpses reporters saw at the start of camp. 

But with Irving struggling to find his offensive rhythm, Heinsohn twice wondered on NBC Sports Boston’s postgame shows whether Irving was out of shape.

"Personally, I think he's a little out of shape. To me, it looks like he's a little overweight, and to me — his timing, his quickness — he's maybe an instant slower than he's been,” Heinsohn said after Boston’s win in New York on October. 20. "With one darting move last year, he was able to get by three people. I don't think he's got quite that quickness back yet, but he's going to come along.”

A week later, Heinsohn doubled down on his assertion.

"He is recovering from an injury. To me, he looks like he's 5 pounds overweight, but I haven't seen him on the scale,” Heinsohn said after Boston’s win in Detroit on Saturday. Later he added, "He's just a half-a-step slow.”

Irving said those comments only encouraged him to improve his conditioning.

"I had to get in better shape and I had to become more dedicated to what I had been doing but more emphasis,” said Irving. "So I took that  -- I was on the bike the next morning, Versaclimb, I was doing everything possible to make sure I could prepare my body for what’s to come for the rest of the season. It’s a long season, just wanted to get prepared. But I shouted him out because that was the truth, I needed it.”

Irving essentially gave Tommy a Tommy Point.

Irving was asked if he planned to try to play in all 82 games this season but admitted he’ll likely miss an upcoming game against the Utah Jazz in order to attend a memorial service for his grandfather. But he admitted that trying to play in as many games as possible is a goal of his.

And he’s clearly getting himself in the sort of shape that will allow him to stay on the court this season. 

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