Here was the devil’s bargain Mets manager Terry Collins faced with two outs in the bottom of the eighth inning Wednesday afternoon at Nationals Park. Reigning National League MVP Bryce Harper was at the plate, representing the tying run. Closer Jeurys Familia was ready to go in the bullpen. Collins, instead, stuck with rookie right-hander Steven Matz. This was a big game for the Mets, as games in May go. But some things matter more than one victory.