Cleveland Cavaliers coach J.B. Bickerstaff will miss Wednesday's game against the Chicago Bulls due to personal reasons, the team announced.
Assistant coach Greg Buckner will serve as head coach vs. the Bulls.
The Cavs said Bickerstaff is expected to return for Friday's game at Charlotte.
Bickerstaff was disappointed with his players' effort in a 109-105 loss to the Detroit Pistons on Monday night as the Cavs fell to 20-37 this season.
"It's a conversation about approach and a maturity level that we've yet to reach," Bickerstaff said of the loss. "The thought that we wouldn't come out tonight and play spirited basketball is disappointing."
He added: "I love the dudes in that locker room. I think their hearts and minds are in the right place. But we've got to grow up. It's that simple."
Larry Nance Jr. missed Monday's game for personal reasons.