- MLS Pool keepers are goalkeepers that are signed by the league but don't belong to any team. Because of the roster limits and the requirement that teams play a keeper MLS keeps 2-3 extra keepers on contract to fill in in case of emergency due to injuries or suspensions.
Supposedly the Rapids have owned Sharpe's rights since he joined MLS, but he was never signed specifically for the Rapids. Sharpe's blog doesn't make it clear if his new contract is only with the Rapids or if he'll continue being a pool keeper. I've sent him a comment asking for clarification and I'll post an update if I get a response.