The only way to do it is to find two Captains that are happy to start the match, but sit it out on the sidelines and not get involved. All four Captain's slots have to be filled, at a minimum. If you see me in the game I'll happily fill one of the slots (and see if I can find someone I know to fill the other), and then go play around the edges of the map whilst you sort out your relationship anger management in the arena.. ..