The San Antonio Spurs will be without head coach Gregg Popovich indefinitely after he reportedly suffered a health issue prior to the team’s last game.

The 75-year-old Popovich didn’t coach the Spurs (3-3) during Saturday’s 113-103 win over the Minnesota Timberwolves due to what the team said was an undisclosed illness.

Mike Johnson took over as head coach against Minnesota and will remain in the role while Popovich is sidelined.

“He's not feeling well,” Johnson said prior to Saturday’s game. “This has happened before.

“I think everybody's just always got to be ready for the next man up. We've had it with injuries and sometimes people get sick or don't feel well or things come up in life.

“He's just not feeling well.”

Popovich is the NBA's all-time leader with 1,391 victories and has won five NBA titles while coaching San Antonio since the 1996-97 season.