Zach Lutz delivers a sixth-inning RBI double.

PORT ST. LUCIE, Fla. -- Jonathon Niese tossed 4 1/3 scoreless innings in his final assignment before Opening Day and Marlon Byrd homered, doubled and drove in three runs as the Mets beat the Houston Astros, 6-2, Wednesday night at Tradition Field.

Niese next opposes San Diego Padres right-hander Edinson Volquez on Monday at Citi Field.

Niese finished spring training with a 1.23 Grapefruit League ERA. During a 74-pitch effort, he limited Houston to two hits and two walks while striking out seven.

“Early in the spring I didn’t really feel like I had all of my pitches going at one point,” Niese said. “But today I felt like I had everything going, especially the curveball. I felt like, for the most part, I could control it and throw it for a strike, and throw it in the dirt when I wanted to. Overall, the arm felt good and I’m ready to go.”

Byrd is hitting .346 in Grapefruit League play.

Scott Atchison surrendered two eighth-inning runs -- one unearned, because of a Jordany Valdespin fielding error at second base. Left-handers Scott Rice and Pedro Feliciano combined for 2 2/3 no-hit relief innings. Bobby Parnell notched the save by striking out the side.