DALLAS -- Alvin Gentry isn't worried about Zion Williamson's conditioning.

Following a frustrating 127-123 overtime loss to the Dallas Mavericks on Wednesday, the New Orleans Pelicans' coach was asked how he thought Williamson looked conditioning-wise as he played his first back-to-back of the season.

"I think he's fine," Gentry said. "We worry about him too freakin' much, OK? He's fine. He's 19 years old. He'll be fine."

Williamson admitted it took him a little longer than usual to get going. Playing in the first back-to-back of his young NBA career, he looked sluggish in the first half, and his teammates -- particularly guards Jrue Holiday and Lonzo Ball -- let him hear about it.

"I think it was just one of those things where Jrue, Lonzo just kinda came to me and was like, 'You ready to play?' because if you saw me in the second quarter, I think I just kinda turned around, looked at Lonzo, like, 'All right, I'm awake now,'" Williamson said following the loss. "Because they just came to me, like, 'It's time for you to wake up.'"

Williamson finished with 21 points on 9-of-18 shooting in a season-high 35 minutes, but those baskets were tough for him to come by. The Mavericks' front line gave him fits early, as he struggled to get going.

The Mavericks used 6-foot-10 Maxi Kleber to defend Williamson for most of the game, with 7-foot-3 Kristaps Porzingis lurking at the rim. Those two combined for 10 blocks. Dallas switched things up by starting both Kleber and Porzingis, specifically to match up against Williamson.

"I thought that Kleber did as good a job as you can do holding ground and trying to make it difficult," Mavericks coach Rick Carlisle said. "We're talking about a guy who has unprecedented strength and explosiveness and a great basketball feel. He's a great, great young player. They do all of the right things in terms of how to get him the ball and utilizing his quickness and speed in transition."

Williamson was blocked three times in the first half and was just 5-of-13 heading into the fourth quarter. He went 4-of-5 in the fourth quarter and overtime, but it wasn't enough to help the Pelicans win. Williamson added that he's used to the physicality from teams, but Dallas was "very physical" with him.

Despite that, Williamson continued to drive toward the rim but managed to shoot only 3-of-5 from the free throw line. Gentry said he thought he should have had more trips to the line.

"I still think if you take the ball that hard to the basket that many times, somewhere along the line, there will be a few fouls," Gentry said. "We'll go back and look at it and see, but that's as far as I'll go with it."

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Kleber, who had five blocks against Williamson, said his legs were still heavy after the game from dealing with Williamson throughout the night, but the help from his teammates made his job a little bit easier.

"They tried to collapse as soon as he gets into the paint," Kleber said. "We don't want to give him easy looks. KP did a great job coming over and helping out. That's the No. 1 thing because guys like him, you can't defend him by yourself."

Despite Gentry's comments on everyone else's worrying about Williamson's conditioning, the Pelicans did have to watch how they used him. Williamson did not start the overtime period and didn't check in until the 1:44 mark.

Williamson will get some much-needed rest Thursday before the Pelicans get back on the floor Friday against the Miami Heat to continue their playoff push.

New Orleans is five games behind the Memphis Grizzlies for the eighth spot in the Western Conference, with three teams -- Portland, Sacramento and San Antonio -- separating them and the Grizzlies.

According to research by the Elias Sports Bureau, only the 1995-96 Washington Bullets made the playoffs after being five games out of the race with 20 games to play -- something the Pelicans will attempt to do.

"Just keep playing hard," said Ball, who finished with 25 points, 11 rebounds and 6 assists while tying a career high with seven 3-pointers. "That's all we can do at this point -- keep playing hard. We need to put ourselves in a position to win."