I'm the wife of a rugby player, so I am right there with you! I actually got into my car a few weeks ago and jumped out about before I even sat all the way down - I seriously thought that an animal had crawled into my car and died, the smell was so bad! Turns out it was his rugby cleats (and jersey, shorts, socks) that he threw in the back of my car after the game, and forgot them there for the weekend, roasting in the sun! UGH!!!
The answer is, store everything in the garage or outside on the patio. You can wash them and put that athlete's foot powder in them, but don't expect it to help that much. I make my husband take his shoes off immediately after the game and put them in a plastic bag - then when he gets home, hose them off in the front yard using the power nozzle and put them out to dry. The trick is to train the athlete do his own clean-up. You will be saving his future wife a lot of headaches! =)