Career
He was 5th at the 2013 Ironman World Championship and was the first American to cross the line. In 2014 O'Donnell announced that he had begun working with Mark Allen in preparation for the 2014 Ironman World Championship. He experienced a disappointing finish at the championship when he experienced stomach pain and walked during the marathon.
O'Donnell married fellow triathlete Mirinda Carfrae in 2013.