Looks like the Red Sox-Cardinals pipeline might not be closed just yet! With Boston shifting top prospect Marcelo Mayer to third, there’s a real opening at second base—and Brendan Donovan, the Cards’ do-it-all guy, is right in the mix. The question: will Boston’s front office pull the trigger, or will defense concerns keep the Don in St. Louis? Either way, this Cards-Sox trade dance is heating up again! #Sports #Baseball #RedSox