Change the food to a high quality grain free food. This will eliminate the odor. If the cat is in such a hurry to escape, it "could" be the odor, or the cat may not be comfortable when going and needs to get away from the 'hurt.' Changing the food will help clear that up as well.

Earthborn Holistics makes grain free cat food. http://www.earthbornholisticpetfood.com/us/

The 3rd possibility is behavior and I have no clue how to train a cat to cover!