In the bottom of the ninth with the bases loaded, Pirates catcher Jacob Stallings swung away at Mets closer Edwin Díaz's fastball and as soon as he made contact the crowd at PNC Park erupted.
Stallings homered to left field to complete the 6–0 comeback and win the game 9–7.
The Mets kept the Pirates scoreless in the first seven frames until a red-hot eighth inning for the home team. Pittsburgh scored five runs in the eighth to make it just a one-run game in the ninth.
Brandon Nimmo homered to center field to give the Mets some cushion going into the bottom of the ninth but it there was blood in the water.
Stallings walk-off grand slam brought home Ke'Bryan Hayes, Bryan Reynolds and Jared Oliva for the storybook ending.
The Pirates improve to 36–56 and the Mets fall to 47–42 on the season.
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