Credit: Photo courtesy of GRAND-AM Road Racing Series Photo: Patrick Dempsey Talks Racing on January 8, 2012

Don't worry, Grey's Anatomy junkies — we're sure Patrick Dempsey is still super devoted to acting, but the on-screen doc admits it's not his number one passion.

Participating in a three-day testing for Rolex Sports Car Series “Rolex 24” at Daytona International Speedway in Florida over the weekend, the Grey's star revealed that his very first passion is racing and not acting.

Patrick, who showed off his natural salt and pepper hair at the testing, also explained that returning for an eighth season of Grey's Anatomy depends on how he could fit the shooting schedule in with his racing career. That’s right, racing career. PDemps is getting serious about racing!

Can't the Grey's producers just write in some kind of racetrack storyline at Seattle Grace, so we can all sleep at night? It's that simple, people!

Remember to tune in to the episode on Thursday, January 12, at 9 pm ET/PT on ABC.

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