By Cody Westerlund–

CHICAGO (CBS) — Time and again in the past month since training camp opened, the rebuilding Bulls have lauded the hard-working, team-first culture they claimed to create. A team completely devoid of stars and proven commodities to a large extent had no other option than to embrace togetherness.

That culture will be tested now in a way none of them anticipated.

On Wednesday, the Bulls suspended third-year forward Bobby Portis for eight games for his actions a day prior, when he punched teammate Nikola Mirotic in the face during a practice altercation. The incident came after the two had scuffled and exchanged words on a handful of trips up and down the court. Assistant coach Randy Brown stepped in once, hoping to dissolve the hostility.

His intervention did little. Shortly thereafter, Portis “crossed a line,” as executive vice president of basketball operations John Paxson said, delivering a one-punch knockout that sent Mirotic to the ground for several minutes and necessitated a trip to the hospital afterward.

It wasn’t a sucker punch, Paxson emphasized. It was an embarrassment at the dawn of a new season.

“Both players owned responsibility in the incident itself, but only one player threw a punch,” Paxson said.

“Deflating” and “inexcusable” were two words big man Robin Lopez used.

“I was shocked,” coach Fred Hoiberg added.

Mirotic is expected to miss four to six weeks, the team said. Before he can undergo the surgery that’s likely needed to repair his two facial fractures, his concussion symptoms have to pass. That could take “some time,” Paxson said.

The Bulls settled on an eight-game suspension for Portis in large part because of the result of Mirotic’s injuries, Paxson said. They did so after a consultation with the league office, but Paxson left no doubt that this was a team suspension. It’s unclear if Portis will appeal the punishment.

As it stands now, Portis won’t be eligible to play until Chicago travels to Toronto on Nov. 7. In the meantime, he can still practice with the team, though he didn’t do so Wednesday. The Bulls told him to stay home and cool off.

As Hoiberg pointed out, the Bulls will be playing about 10 percent of their season severely short-handed. Mirotic and Portis join Zach LaVine, Kris Dunn and Cameron Payne on the list of those missing the weeks to come.

Rookie Lauri Markkanen will start at power forward in the season opener at Toronto on Thursday, Hoiberg said. On a roster with 17 players to choose from when including those with two-way contracts, the Bulls will only have three true big men available for the first eight games.

“I’m very disappointed in what happened,” Hoiberg said. “Now, my job is to not let this moment derail us. My job is to get these guys prepared to go out and fight and play as a group, and I’m confident our guys will do that.”

For a rebuilding team, the long-term ramifications are more unsettling than any rut of losses in the near future to open a season. The 22-year-old Portis is entering a pivotal third season after he flashed promise as a rookie, only to see his development stunted as a sophomore. The Bulls have until Oct. 31 to pick up his fourth-year option, which is usually a formality for first-round picks.

Portis — who as a rookie cited Kevin Garnett as one of the players he modeled his game after — has been widely praised by coaches and teammates for his work ethic and passion, but this marked a worrisome case of his competitive fire burning too hot. Portis was outplayed by Mirotic and at times Markkanen in the preseason. He has been behind Mirotic at power forward on the depth chart for most of the past two seasons, and it couldn’t have been easy on him to see the Bulls use a lottery pick to draft Markkanen as a foundational piece of their rebuild in June.

Asked how this incident affects Portis’ long-term future with the team, Paxson demurred.

“As I said Bobby Portis is a good young man,” Paxson said. “He is just a tough, competitive guy. These are some of the things we valued with him. We haven’t even thought about that, no.’’

For Mirotic, it’s a needless setback once again inflicted by someone else in or affiliated with the organization. His second season was stunted when he had complications from an appendectomy in late January 2016, forcing a second surgery for a hematoma removal. He lost nearly 20 pounds then and encountered a difficult road to feel like himself again.

Inconsistent throughout his three-year NBA career, Mirotic signed a two-year, $27-million with a team option on the second season just before the start of training camp in September, looking to alter his reputation and prove his worth. In years past, Mirotic has admitted to being too tough on himself mentally, to the point that it affects his play. This will prove challenging once again.

“Niko, he’s hurting,” Hoiberg said. “No doubt about that.”

Before the regular season has even started, doubt now has a window to permeate the Bulls. On the eve of the opener, Paxson and Hoiberg were left to answer questions as to whether they allowed hostility to fester for too long, if the coaching staff had proper command of the team.

“Hindsight’s 20-20,” Hoiberg responded, aware that the Bulls’ culture rooted in being there for one another has now been dented.

Cody Westerlund is a sports editor for and covers the Bulls. He’s also the co-host of the @LockedOnBulls podcast, which you can subscribe to on iTunes and Stitcher. Follow him on Twitter @CodyWesterlund.

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