Travis d'Arnaud clubbed a three-run shot, while Curtis Granderson added a two-run blast and drove in three for the Mets, who have won their last three straight games.
Bartolo Colon (8-5) scattered four hits and one run while striking out eight over eight strong innings against the team he pitched for the previous two seasons.
Yoenis Cespedes knocked in the lone run for the Athletics, who have lost two in a row following a five-game win streak.
Scott Kazmir (9-3) was punctured for eight hits and seven runs over just three full frames in defeat.
Notable deaths of 2014 [PHOTOS]