San Antonio Spurs assistant coach Mitch Johnson is expected to serve as the interim head coach indefinitely while head coach Gregg Popovich is dealing with a "health issue," according to ESPN's Shams Charania.

Charania reported the situation for Popovich arose before Saturday's 113-103 win over the Minnesota Timberwolves. The 75-year-old wasn't on the bench due to an undisclosed illness.

"Mitch did a great job," point guard Chris Paul said after the victory. "Things happen within this league all the time, and just like with players it's 'next man up.' So shout out to Mitch."

Johnson began his coaching career in 2016 with the Austin Spurs of the NBA G League. He moved on to San Antonio in 2019 and steadily moved up the bench with the departures of Tim Duncan, Becky Hammon and Will Hardy.

Popovich's reputation precedes him. He's widely regarded as one of the greatest head coaches ever, boasting five titles and an all-time record of 1,391 wins in the regular season.

With the Spurs heading toward 22 wins and a total rebuild in 2022-23, it looked like his legendary career was starting to wind down. Then San Antonio won the 2023 draft lottery and earned the right to take Victor Wembanyama first overall.

Perhaps not coincidentally, Popovich penned a five-year deal reportedly worth more than $80 million ahead of the 2023-24 season. That eliminated any doubt about his short-term future.

The Spurs matched their 22-60 record despite Wembanyama's arrival and his immediate emergence as a one-of-a-kind talent. Their 3-3 start points to what should be some progress on the court this year.