PORT ST. LUCIE, Fla. — The Mets are dealing with a 1-2 gut-punch. A day after Jacob deGrom learned he would be shut down from throwing for up to four weeks, Max Scherzer was scratched from his Saturday start in an intrasquad game with right hamstring tightness. Scherzer said he considers himself day-to-day, but he isn’t sure when he will pitch again. Now, his opening-day start is in question. “It’s frustrating,” Scherzer said. “I’ve really worked hard this offseason to really lift my legs heavy, do all the running. I felt like I was in a really good spot with my body and my arm. And it’s frust…