Priority No. 1 for Bulls coach Billy Donovan: Teach this roster winning

It has only been a few weeks, but his players already have gotten a good sampling of Billy Donovan’s many facets.

After a comeback victory Friday in the Bulls’ preseason finale, they witnessed a coach who was glad to see his backups overcome a lethargic night by his starters and one who let those same starters know that taking nights off defensively will not be tolerated.

There were no push-ups or suicide sprints, but his tone let them know who the boss is and why that boss warrants respect.

“What I like is he [has a commanding] presence,’’ guard Zach LaVine said. “He’s very straightforward. You can tell if we’re doing good or bad, obviously. He wants us to fight. He brings that out of us. He’s encouraging us to be competitive and bring it every night. I’m trying to take it upon myself to get the group going in the beginning. He’s good for us. He knows what he’s doing.’’

Asked if Donovan was a screamer a la Jim Boylen, LaVine smirked.

“I wouldn’t say that,’’ LaVine said. “But when he talks, everybody listens. He definitely commands the room.’’

With four preseason games in the books, the games start to matter this week. The Bulls begin the regular season Wednesday night against the Hawks at the United Center.

Donovan has been trying to stress many things, but atop that list is understanding what it takes to play winning basketball throughout a season and having the mental toughness to achieve that. It sounds simple, but for a roster mostly made up of players who’ve never even sniffed the postseason, it could be a monumental task.

“A lot of times because we have really good guys that want to do well and do the right thing, sometimes they can get deflated,’’ Donovan said. “And we’ve got to understand that there are going to be 100 possessions on offense and 100 possessions on defense, and not every possession is going to go well. We have to have a level of resiliency, mental toughness, mental fortitude to fight through difficulties.

“That’s not just the case for our team; it’s the case for any team playing in the most competitive basketball league in the world. You’re going to have to deal with those things. So with a younger team, we’ve got to get better at those things, and we’ve got to improve collectively.’’

Roster cleanup

The Bulls got their roster down to 15 guaranteed contracts, waiving Zach Norvell Jr. and Simi Shittu, Friday’s second-half hero, on Saturday morning. Devon Dotson and Adam Mokoka are two-way-contract players, although Mokoka was having trouble joining the team because of travel restrictions.

The team also announced it exercised the third-year option on guard Coby White and the fourth-year options on center Wendell Carter Jr. and forward Chandler Hutchison.