I am pretty sure the Yankees trained in Fort Lauderdale until the 1990's when Steinbrenner Field was built. Tampa I think was Reds training ground. The Mets and especially the Cardinals trained in St Petersburg. The big reason the Rays played in Tropicana Field instead of Tampa is that Pinellas County has a pile of cash from tourist bed taxes, and Tampa/Hillsborough doesn't. Unless private money steps forward to build a stadium in Tampa, and they couldn't find that after a year of looking once before, they are probably going to need to relocate. The San Francisco Bay Area has 6 million people and an MLB stadium ready NOW, and an abandoned Oakland fan base that will be grateful to be back in the bigs. Market 4 is big enough to support two teams. Unless Tampa money is found (Jeannie, Jeannie), or unless Pinellas has a change of heart over committing tax dollars to the less-than-straight-shooting Rays ownership, relocation somewhere else is very likely.The Devil Rays, simply Rays now, did not exist when I was growing up there in the 60s but The Yankees training facility was there so got taken to a few exhibition games there. As a default, many Tampa Bay kids rooted for the Yankees as the "hometown" team.
Bringing it back to Radio - do cities that lose teams have any support or broadcasting on their radio partners left behind? Will whoever carried the Oakland A's continue to run the Sacramento A's? Did St Louis have a station carrying the LA Rams for any period of time?