MIAMI — The Miami Marlins were barely done celebrating Sixto Sanchez’s first career complete game in Game 1 of their doubleheader against the Philadelphia Phillies when they laid out their plan for Game 2: Braxton Garrett, the No. 4 pitching prospect in the organization, was going to make his debut just 30 minutes after Sanchez, the Marlins’ No. 1 prospect, finished up maybe the most impressive outing of his young career.Miami is in the thick of a playoff race, well positioned to make the postseason for the first time since 2003, and the Marlins placed one of the most important days of their s…
