This is not a question I ever thought I would need to ask, but after leaving a pair of muddy football boots overnight on the decking by the back door it became apparent that a tom cat had decided to mark its territory by spraying them liberally. They have been washed twice and after letting them partly dry out tonight it seems the smell is as bad as ever. Any suggestions? They are almost new and will have to be thrown away if we cannot stop them stinking the house out 