Losing two outfielders in the same week is not how the Mets expected their home stand to play out. Brandon Nimmo limped off the field, alongside a trainer and manager Buck Showalter, after the seventh inning of the Mets’ nightcap against the Cardinals in a doubleheader on Tuesday at Citi Field. Nimmo fouled a ball off his knee during his at-bat against Cardinals southpaw Genesis Cabrera with two outs in the seventh.