Nerlens Noel hasn’t seen a lot of playing time recently. The fourth-year center finds himself out of favor in head coach Rick Carlisle’s rotations. In the four games leading up to Wednesday, Noel played a total of 11 minutes and 31 seconds. In Saturday’s contest against the Cleveland Cavaliers, he didn’t even get in the game. Noel’s current limited role isn’t set in stone, but there are a number of reasons contributing to his time spent mostly on the bench of late.

For starters, Noel’s teammates are simply out-playing him. After Salah Mejri openly complained about his playing time, he’s had the opportunity to prove himself. In the last four games that Noel saw his minutes decline, Mejri saw an uptick. He played an average of 15 minutes compared to Noel’s 4.2. Mejri’s effort and energy on the floor along with averages of 5.8 points, six rebounds, and two blocks during this span kept him in games.

“Salah’s earned the minutes at this point,” Carlisle said.

It’s not just Mejri that’s eating into Noel’s potential minutes. Dwight Powell is seeing extended playing time at center this season. Recently, Maxi Kleber, the 25-year-old rookie from Dirk Nowitzki’s hometown of Wurzburg, Germany, also broke into the rotation.

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Against the San Antonio Spurs on Tuesday night, Kleber played almost 21 minutes. In that time, he totaled five points, one rebound, and one block. While it’s not the most impressive stat line, his effort was apparent. Two of his points came off a baseline driving dunk and his block was equally highlight reel worthy.

“Minutes are earned,” Carlisle frequently says. And so far, these are the guys earning their time on the floor. With a roster replete with big men, the optics don’t look great for Noel when he’s in the game.

If you believe Carlisle, matchups also factor into why he’s keeping Noel on ice. In today’s NBA, the center position is more of a hybrid with bigs stepping out and playing around the perimeter. If you believe Noel, though, this isn’t a problem for him.

“I think I can matchup on anybody,” he said.

If that’s the case, he’s not getting much leeway to prove it. The issues Noel is facing go beyond his effort and matchups, though. The effort is there. He’s been putting in extra work in practice of late. What’s dogged him this season, to the naked eye at least, is his understanding of his role on the floor. He’s caught out of place and ball-watching far too often on defense. That can’t happen in the Mavericks’ system.

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“The No. 1 job in coaching is to keep role definition simple, decisive, and make sure that everybody 100 percent knows their job,” Carslise said. “The system means that there is help built into it as long as you do your job. If you go outside the system and start breaking rules willy-nilly, you’re not going to have help built in for you and then there’s problems and you’ve got to get guys out of the game.”

Noel will get a chance to prove himself eventually. If he’s putting in the work in practice, it’ll earn him playing time. However, until that time comes, Noel will keep himself ready and won’t hang his head even if this isn’t the role he envisioned for himself coming into the season.

“Disappointed isn’t a word for me,” Noel said. “Just keep pushing, keep working on what I got to work on, and just keep my mind right. And when I go out there, I’m going to play my hardest and give force to a winning effort every time.”