It’s almost hard to remember this, but Robin Lopez began the season as the Bulls’ starting center. The box score from the Sept. 30 preseason game against the Pelicans proves it.

Lopez, conventional wisdom went, would serve as the veteran mentor and starter as the Bulls brought first-round pick Wendell Carter Jr. along at the proper pace. Carter, 19, could be brought along slowly, learn from a rugged, fundamentally sound big and eventually take over the position, most likely as the Bulls shopped Lopez ahead of the February trade deadline.

Instead, Carter beat out Lopez in the preseason. And, in a more surprising development, Cristiano Felicio leapfrogged Lopez in the rotation over the last three games.

Yes, Lopez, he of the $14.3 million expiring salary, is now drawing “Did Not Play, Coach’s Decision” designations.

Lopez drew these as well after the All-Star break last season, back when his T-shirt game was strong and the Bulls jostled for draft lottery positioning. But this is less about pingpong balls and more about performance.

“It’s with purpose,” Lopez said. “Wendell and Cris are doing specific jobs and they’re doing them well.”

Felicio even closed over Carter despite Carter posting his first double-double in Saturday’s victory against the Hawks in Atlanta. It’s a welcome reprieve for the forgotten Felicio, who is resembling the active, athletic reserve on whom the Bulls bestowed a four-year, $32 million deal when free agency began in July 2016.

Photos of Bulls center Robin Lopez.

“I fully planned to get Wendell back out there,” coach Fred Hoiberg said. “I thought he was terrific. But so was Cris. Cris is doing the little things. He’s rolling to the basket. He’s doing a better job of staying flat on the floor (defensively). He’s running the floor well. He’s moving his feet defensively. I thought he was great in our (pick-and-roll) blitz scheme. His ability to stay in front and his hands were really good; he got some deflections.”

Befitting his team-first reputation, Lopez is openly encouraging of both Carter and Felicio during games. During one timeout Friday in Charlotte, Lopez even hugged Felicio. And he could be seen talking to Carter during another.

However, Lopez privately was frustrated enough by the demotion that he has had several closed-door meetings with members of the coaching staff, sources said. Hoiberg, in particular, has drawn internal praise for directly diffusing Lopez’s frustration.

“What NBA player wouldn’t want to be playing?” Lopez said. “But I realize we’re trying to do what’s best for the team right now.”

The fact that Lopez has looked a step slow this season won’t help his trade value at a time when traditional bigs are mostly falling by the wayside. The Bulls have consistently mentioned their belief that the trade value of expiring contracts will bounce back.

Lopez in particular struggled in Dallas, his last game in the rotation. He drew a technical foul for colorfully telling an official: “Don’t give me those (expletive) platitudes!” But he also incurred foul trouble for the second time in three games, somehow drawing five personals in 9 minutes, 30 seconds.

“I would hope I could help the team,” Lopez said when asked where he thought his play stood.

So Lopez sits and waits, wearing a uniform that doesn’t get sweaty instead of the T-shirts he sported during his inactive periods last season. Like then, he tries to be a good teammate.

“My teammates do the same for me,” he said. “When I’m out there playing, they support me. They root for me. I’d be a jackass not to be supportive of them. Whatever I can do to help the team, I’m going to do it.”

kcjohnson@chicagotribune.com

Twitter @kcjhoop

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