Tony Stewart was off on his own this week, racing at the Front Row Challenge at the Southern Iowa Speedway in Oskaloosa, IA. Unfortunately, things didn't turn out so well, as he was involved in a crash and broke both his right tibia and fibula, according to USA Today. Only five more laps remained in the race, but Josh Higday's spun out and took down four people with him. We know Stewart is a determined guy, but it's pretty safe to say that he'll be missing the NASCAR Sprint Cup race at Watkins Glen this weekend. 

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[via USA Today]