Marcus Gronholm to miss penultimate round of Global Rallycross Championship in Las Vegas

Gronholm underwent a medical at the end of last month and will take further tests early in October before deciding whether to return to his OMSE Ford Fiesta for the final round of the championship on October 30 in Las Vegas.

Gronholm was knocked unconscious in the X Games crash and admitted last month that he was still undecided about returning to the sport.

His car will be driven in Nevada this weekend by his team boss Andreas Eriksson.

Gronholm said: "I have worked hard on my rehabilitation since the accident at the X Games at the beginning of July.

"I feel fine, however doctors set a date in October in order to ensure I am 100 per cent fit, so I cannot compete in Vegas and I will wait until the assessment before thinking about my next step.

"I will however be in Las Vegas, and I can think of nobody better to fill in for me and keep the challenge alive than Andreas. He is fast, but I can still give him some tips!"

Gronholm said he had no intention of walking away from motorsport completely. The double world champion is considering various options for 2013.

He added: "Of course competing in a car in some shape or form is my preferred option, but I have been busy developing lots of ideas for next season, some involving active competition, some involving different roles outside of the car, which will be quite different for me, but still will be exciting and challenging in equal measure.

"This way I can move forward with a clear plan regardless of the doctors' verdict next month."