I had a friend who damaged her bike the day before a century, and borrowed a friend's bike for the century. She got to the start and asked me to change the pedals to her pedals but I could only get one of them off - her son had tried to remove them and rounded off the flats on one. So she rode the whole thing with one sneaker and one foot clipped in.
Wound up buying her friend a new set of pedals and cutting the old one off.