The Mets won their fourth in a row despite getting only three hits. The NL East leaders have won seven straight regular-season games against St. Louis overall.
Green connected for his seventh homer, sending a full-count pitch from Russ Springer (3-1) off the scoreboard in right-center field. It was the Mets' first hit since Carlos Gomez homered in the third inning.
Aaron Heilman (6-3) pitched one inning for the win. Last fall, he allowed Yadier Molina's ninth-inning homer that gave the Cardinals a 3-1 win and sent them to the World Series.
Minus the playoff drama and much action, the crowd of 40,075 had little to cheer for most of the night. The Mets went seven innings without a hit against St. Louis newcomer Mike Maroth and reliever Ryan Franklin while the banged-up Cardinals had ample soft outs, too.
Traded from Detroit to St. Louis last Friday for a player to be named, Maroth did everything in his NL debut except win.
Maroth quickly introduced himself to catcher Gary Bennett -- gesturing what each of his first eight warmup pitches would be
-- and then shut down the Mets on two hits for 7 1-3 innings.
Throwing barely over 80 mph, he got Jose Reyes and others to take several awkward swings. Maroth helped himself by catching a pair of runners leaning the wrong way and picking them off first.
Maroth neatly slapped a single in a bunt situation -- injured teammate David Eckstein offered his bat before the game
-- put down a sacrifice bunt and stole his first base in the majors. Maroth also did something equally rare, drawing applause from Mets fans when he exited during a double switch.