NEW YORK — It started in the grayest of areas, a debate Tuesday about which team has the permission to concede first in a blowout, and it escalated Wednesday with a 34-second home run trot that sent the clearest of messages.



This dormant rivalry was invigorated by — of all things — baseball’s unwritten rules. A decade has passed since both the Phillies and Mets held conceivable postseason hopes at the same time. Hate slumbers when the games are irrelevant.



“I think that’s what rivalry is,” Rhys Hoskins said after a 6-0 win. “I think there’s always going to be a little bit of bad blood in a rivalry.”



Jake Arrieta, from across the Phillies clubhouse, heard those words. “He said it!” Arrieta yelled.



Down the corridor at Citi Field, while the Mets said the right things publicly, one privately stated the subtext. “It’s definitely not going to be...