Team Logo. The Waterloo Diamonds were a team in the Midwest League. They were the Low-A affiliate of the San Diego Padres. In 1994 they moved to Illinois and became the Springfield Sultans. Retrieved from "https://prosportsteams.fandom.com/wiki/Waterloo_Diamonds?oldid=10058" Categories: Former MWL Teams Teams in Iowa Add category Cancel Save Community content is available under CC-BY-SA unless otherwise noted.