Wright lined an early RBI single that extended his hitting streak to 12 games and Kyle Farnsworth earned his first save as the New York's newest closer.
On an evening when the Mets debuted new camouflage tops to salute the military, they looked sharp. The Cardinals lost for the third time in four games.
Mejia (3-0) bounced back well from a torn blister on his right middle finger that limited him to five innings in his last start. The 24-year-old righty began the game by getting Matt Carpenter to look at three straight strikes, and rarely was in trouble.
Tyler Lyons (0-1) lost in his first major league game of the season. Promoted from Triple-A Memphis earlier in the day to take the rotation spot of injured Joe Kelly, he allowed two runs and six hits in six innings.
A 26-year-old lefty with a big-breaking slider, Lyons struck out seven. He's another in the long line of tall, homegrown pitchers developed by the Cardinals, and went 2-4 last year in his first big league season.
The previous inning, the Mets backed Mejia with a sweet double play. Shortstop Ruben Tejada dived to stop Jon Jay's grounder up the middle and flipped to Murphy, and the second baseman made a barehanded catch and spun quickly for the relay.
NOTES: Wright has eight hits in his last three games. He has eight RBIs in eight games. ... Cardinals C Yadier Molina stretched his hitting streak to 12 games. ... Granderson struck out three times. He's hitless in his last 19 at-bats and is in a 4-for-47 slump that includes 17 strikeouts. ... St. Louis SS Jhonny Peralta was hitless in three at-bats and is in an 0-for-15 rut. ... The Mets promoted 40-year-old OF Bobby Abreu from Triple-A. He didn't get into the game. ... St. Louis RHP Eric Fornataro made his major league debut and pitched a perfect eighth. Molina waited outside the dugout to pat him on the head. ... Cardinals RHP Adam Wainwright (3-1, 1.80) starts Tuesday night against RHP Dillon Gee (1-0, 3.71) in the second game of a four-game series. ... Kelly strained his left hamstring trying to beat out a bunt last week and was put on the 15-day disabled list.