Timberwolves associate head coach Sam Mitchell will lead the team while Flip Saunders recovers from cancer treatment.

The Wolves have temporarily promoted the NBA's 2007 Coach of the Year back to a head-coaching job while Saunders fights Hodgkins lymphoma, according to a source with knowledge of the situation. The Wolves on Thursday said they'd make a "major announcement" at a Friday news conference.

The length of Mitchell's appointment as interim head coach is uncertain and based upon Saunders' health and recovery. It's expected to be at the very least through October, which includes training camp, a seven-game preseason schedule and the season opener Oct. 28 against the Lakers in Los Angeles and could be months longer.

Yahoo!Sports reported Mitchell will coach at least half the season, although that hasn't be definitively determined, according to the source.

Training camp begins Sept. 29 at the team's new Mayo Clinic Square facility.

Mitchell, 52, now will lead a staff of assistant coaches that includes Saunders' son Ryan, former NBA head coach Sidney Lowe, David Adelman and recently hired Bryan Gates, who was an assistant under Monty Williams in New Orleans.

Saunders, 60, is believed to have completed chemotherapy treatments but continues his recovery from a cancer of the immune system.

The team last month announced Saunders had been receiving treatment since early June for what doctors deemed a "very treatable and curable form" of cancer. It also indicated Saunders would continue both of his jobs — head coach and president of basketball operations — uninterrupted.

At the time, team owner Glen Taylor said he didn't expect any changes in the team's coaching and basketball operations.

"I don't think it will impact him at all," Taylor said then. "We can work around his schedule."

Taylor did not return a message seeking comment on Thursday.

Now Mitchell will coach a team built around consecutive No. 1 overall picks Andrew Wiggins and Karl-Anthony Towns, and General Manager Milt Newton's role likely will continue to expand in player personnel matters while Saunders focuses on his health.

Mitchell coached two games last season when Saunders was ill for a January game against Denver and in March when Saunders missed a game at Toronto so he could be with his ailing father in Cleveland.

On the day Saunders' cancer diagnosis was announced last month, Wolves veteran guard Kevin Martin likened the situation to former coach Rick Adelman's absences when he took leave from the team while he and his wife, Mary Kay, sought a diagnosis for her seizures.

"Something like that brings the whole team together," Martin said then. "Something like this goes beyond basketball, that's real life. We all take care of each other. We're a family and this is a time to come together like a family."

Mitchell played 13 NBA seasons, 10 of those with the Wolves. He was a member of the 1989 inaugural expansion team and then returned from Indiana to play his final seven seasons with them. He arrived just in time to mentor a rookie named Kevin Garnett, whom he now will coach after Garnett signed, at age 39, a two-year, $16.5 million contract extension in July.

Mitchell coached Toronto for four-plus seasons in the mid-2000s and was named NBA Coach of the Year in 2007. His team won 156 games and lost 189, a career .452 winning percentage. The Raptors made the playoffs twice in his four full seasons there before he was fired after an 8-9 start in December 2008.

He was given the title of Wolves associate head coach when he was hired as one of the team assistants in June 2014 after Saunders decided he would coach the team as well as manage it.