Zach LaVine will miss the next two to four weeks, leaving the Bulls without their top scorer.
LaVine injured his left ankle last week during the Bulls' loss to the Magic in Mexico City.
Coach Jim Boylen called it a lower ankle sprain of the deltoid ligament.
"That's an unusual sprain," Boylen said. "I'm sure they will be very cautious with it and make sure his ankle is stable before we get him back."
LaVine was at the Bulls' shootaround Wednesday at the Advocate Center, lifting weights and "doing all the things he's supposed to be doing. That's what we need," Boylen said.
The Bulls (7-24) have been wrecked by injuries this season, as Lauri Markkanen, Kris Dunn and Bobby Portis have missed large chunks of the season. Denzel Valentine is out for the season.
Wednesday night they host the Nets (14-18), who have won six in a row after losing eight straight.
Asked about the challenge of playing without LaVine, who is averaging 23.8 points, 4.9 rebounds and 4.8 assists, Boylen replied: "We would like everybody to play their minutes with an attitude of unselfishness and sharing, whether you're a screener or a shooter in that play. Share it, move it. Obviously Kris Dunn is a big part of our team. ... Lauri Markkanen, Bobby Portis, right on down the line. Justin Holiday needs to make shots for us. (Ryan Arcidiacono) needs to do what he does. We need a lot from a lot of guys and we hope to get that tonight."
Boylen also said that Jabari Parker is still bothered by a stomach ailment from the Mexico trip.
