Celtics' Brad Stevens out to visit ill ex-Butler center Andrew Smith

— -- Boston Celtics coach Brad Stevens left the team Thursday to travel to his native Indiana and will miss Thursday's game against the Bulls in Chicago.

Stevens made the trip to visit Andrew Smith, a center who played in the  Butler Bulldogs' two national championship game appearances when Stevens was their coach.

Smith has been battling non-Hodgkin lymphoma. He was scheduled to undergo a bone-marrow transplant Thursday, according to The Boston Globe.

Assistant coach Jay Larranaga will serve as head coach for Boston on Thursday.

"We ask that the private nature of this visit be respected," the Celtics said in a statement.

Smith, 25, has been readmitted to the hospital amid a two-year battle with cancer, according to The Indianapolis Star. He was diagnosed with non-Hodgkin lymphoma in January 2014, according to the report.

Smith's wife, Samantha, asked for support Wednesday on social media.

Stevens reportedly visited Smith in November while the Celtics were in town to play the Pacers, two days before Smith was to receive a previous bone-marrow transplant.

Larranaga said he found out late Thursday morning he was filling in for Stevens and was not sure when Stevens would rejoin the team.

Information from ESPN staff writer Chris Forsberg and The Associated Press was used in this report.