Alonso's moonshot came in the second at-bat of the 6-4 setback Sunday at Busch Stadium in St. Louis. Hudson struck out Brandon Nimmo on four pitches to start the game, before Alonso stepped into the batter's box.
The 6-foot-3, 245-pound first baseman took a sinker for a ball on the first pitch of the exchange Hudson then tossed in an 88.5-mph slider. Alonso watched the pitch come right over the middle of the plate, before he turned on it and smacked the ball to dead center field.
Cardinals center fielder Dexter Fowler initially decided to move back for the fly ball, before realizing it was flying way over his head. Fowler turned and watched as the ball landed about 10 rows up into the stands.
Alonso's solo bomb had an exit velocity of 114.5 mph and a launch angle of 30 degrees.
The rookie slugger went 2-for-4 with an RBI, a run scored, a strikeout and a walk in the loss. He is now hitting .325 with eight home runs and 19 RBIs in 21 games this season.
The Mets host the Philadelphia Phillies in a three game series starting at 7:10 p.m. Monday at Citi Field in Queens.