OAKLAND, Calif. — Chicago White Sox manager Tony La Russa says he is recovering well from having a pacemaker inserted for his heart and is uncertain when he’ll return to run the club.

La Russa was back with the White Sox in Oakland on Sunday to celebrate Dave Stewart having his No. 34 jersey retired by the Athletics. La Russa was there for the ceremony but not to manage his team.

The Hall of Famer, who turns 78 on Oct. 4, shared specifics of the procedure with The Associated Press after discussing his health before Chicago’s series finale against the Athletics. He said he is grateful to have had what he considered a relatively “simple” heart issue.

“Health is nothing to mess with,” La Russa said, standing in the dugout wearing jeans, sneakers and a short-sleeve collared golf shirt. “So I got checked in Chicago and the reason that I flew to Arizona is that’s been the place since the ’90s I’ve had my physicals. They addressed it, they fixed it and now it’s just a question of regaining strength.”

La Russa didn’t want to miss the special day for Stewart, his longtime ace with the A’s. La Russa is uncertain when he will be in uniform again and back in the dugout. Bench coach Miguel Cairo has been leading the club during La Russa’s nearly two-week absence. They have been speaking twice a day, and La Russa watches every game from home until he is cleared to do more. He said he had an issue at spring training, too.