Originally Posted by elx
the alternative option is to allow teams to exchange a carded player with a fresh player off of the bench. this could be used as an advantage, a free substitution is enough incentive to purposely receive red cards and exploit it.
That's not the only other option. The teams are obviously allowed substitutions late in the match (if they have them available) - Why not mandate that when a player gets redcarded, the opposing team gets a freebie substitution and the opposing player gets sent to the showers (with a sub in his place)? Or a 5 minute penalty (temporary 11-on-10) à la hockey?
I'm no expert, but both of these seem more reasonable than 11-on-10 for the remainder of the match.
EDIT: I just thought of a third option - how about instead of a 5 minute penalty-box situation, you make him run 10 laps around the field. He can take as long as he wants, but the longer he takes, the longer the team is forced to defend with a man disadvantage. And, if he runs really fast to limit the disadvantage, he gets really winded upon joining up with the team after he completes his laps.
That would also give the crowd ample chance to heckle him as he makes his way around the grounds.
To my Philadelphia sensibilities, this sounds like a win-win.