Who throws a shoe? Apparently, someone at Montreal.

While Danica Patrick was leading Saturday's Nationwide Series race at the Circuit Gilles Villeneuve, a spectator threw a shoe onto the track, and the shoe landed in the racing groove. As Patrick led the field back to the spot where the shoe was, she ran it over squarely and its remains shot out from underneath her car.

It looked innocuous enough — it's just a sneaker, right? Well, Patrick's car immediately started to lose the handling and eventually, what looked to be a bracket or a bolt came out from underneath her car. Her chances at the win were over. She finished 26th, six laps down.

Justin Allgaeir won the race.

The shoe was the bizarre conclusion to Patrick's adventures in the three Nationwide Series road course races this season. In the first, at Road America, she was spun by Jacques Villeneuve (Gilles' son) on the final lap while running fourth. Last week at Watkins Glen, she was collected in a wreck not of her own doing on the first turn of the first lap of the race. She finished last.

Before Saturday's sole incident, Patrick had one of the day's best cars, and after taking the lead through pit strategy and a timely caution, had cleanly held on to it. Patrick has shown flashes of competitiveness at times in 2012 — especially on road courses — but crashes and incidents like the one on Saturday have been the story of her season. Through 22 races she has failed to finish six times and is 11th in the points standings.

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