SHR executive VP Brett Frood says Tony Stewart is grieving and won't return until he's ready

Canandaigua Motorsports Park is seen Monday, Aug. 11, 2014, in Canandaigua, N.Y. On Saturday night, Tony Stewart struck and killed Kevin Ward Jr., 20, a sprint car driver who had climbed from his car and was on the track trying to confront Stewart during a race at the track in upstate New York. Ontario County Sheriff Philip Povero said his department's investigation is not criminal and that Stewart was "fully cooperative" and appeared "very upset" over what had happened. (AP Photo/Mel Evans) (The Associated Press)

The executive vice president of Stewart-Haas Racing says Tony Stewart is grieving — and it will be up to the star driver to decide when he's ready to get back in the car.

Jeff Burton will drive the No. 14 car in Stewart's place in Sunday's NASCAR Sprint Cup race at Michigan International Speedway. SHR executive VP Brett Frood says they haven't discussed any other races.

Stewart is skipping a second straight Cup race since striking and killing driver Kevin Ward Jr. at a dirt-track race in New York last weekend. Frood did not say where Stewart was Friday, but he said Stewart was surrounded by his closest friends and family.

Frood says it was Stewart's decision to skip this weekend's race.