For one night, at least, Ervin Santana looked that good good enough to shut out the Mets for eight innings, in his Braves’ debut. Obviously, that level of performance won’t last, but the already-thriving Atlanta rotation got a boost Wednesday night when Ervin Santana, who was signed to a one-year deal in mid-March in the wake of the Medlen and Beachy injuries, made his Braves debut. Quick quiz: Which team has the lowest rotation ERA in the major leagues heading into Thursday’s action? Would you believe it’s the Atlanta Braves, and that it’s not even close? This is the same rotation that lost Kris Medlen and Brandon Beachy to Tommy John surgery in consecutive spring starts after losing Tim Hudson and Paul Maholm to free agency over the offseason and, just two weeks ago, was choosing between non-roster leftovers Freddy Garcia and Aaron Harang for the fourth, not fifth, spot in their Opening Day rotation.