matt harveyA few years from now, or perhaps in July, this battery could be a big deal. Matt Harvey and Travis d’Arnaud represent the Mets’ future, and today they provided a glimpse.

Harvey, already in the rotation, gave up two runs in 5.1 innings and was backed by two hits and two runs scored by d’Arnaud in a 3-2 victory today over St. Louis. In an 80-pitch effort, of which 54 were strikes, Harvey struck out six and gave up six hits. Spring training is a progression and today Harvey saw an improvement in his breaking ball.

Of course, being a perfectionist, he wasn’t totally satisfied.“I was really happy about my curveball,’’ Harvey told reporters in Jupiter. “Unfortunately, I gave up too many hits in my mind, but overall I’m healthy and feeling good.’’

Harvey made a good impression in ten starts last year with his fastball and composure, but went into the off-season wanting to improve his breaking ball and change-up.

“The biggest thing from last year was not having my curveball,’’ Harvey said. “I threw a lot of good ones and was able to throw it in the dirt when I needed to. That’s a big pitch for me. Having that back is definitely a big plus for me.’’

travis d'arnaud springHarvey has a 2.95 ERA this spring with 24 strikeouts in 18.1 innings. Over a strikeout an inning is a tremendous ratio, but he is smart enough to realize it is better to get an out on one pitch instead of three. Harvey said 200-plus innings is a goal, and to reach it he must go deep into games by keeping his pitch count down.

“I’m starting to learn that a groundball is just as good (as a strikeout),’’ Harvey said. “Going deep into a game is on my mind. If I go seven or eight innings with three strikeouts, that’s seven or eight innings.”

The Mets gave up Cy Young Award winner R.A. Dickey to get d’Arnaud, who they regarded as the key to the deal. When speaking of the other, each said the pitcher-catcher relationship is a matter of chemistry, and so far they’ve clicked early.

“It’s a matter of working together and getting on the same page,’’ Harvey said. “In three starts with him, it’s almost like we’ve been with each other for a couple of years.’’

D’Arnaud is ticketed for Triple-A Las Vegas, but the Mets have given him the privilege of sticking around and making him feel like he belongs in the Mets clubhouse. What he liked best about Harvey today was his poise and command.

“I thought he had a tremendous day, especially with this curveball,’’ said d’Arnaud, who will be developing a working relationship with the Mets’ other pitching prospect, Zack Wheeler, soon enough.

Wheeler strained a right oblique muscle, Feb. 27, and pitched for the first time since today in a minor league game.

Wheeler posted on his Twitter account: “ Felt good to get back in a game today. Tossed three innings and one hit. Felt great.’’

METS MUSINGS: Lucas Duda homered and Bobby Parnell pitched a scoreless ninth inning after giving up six runs in his previous three games. … Ruben Tejada’s miserable spring continued with an 0-for-4. He’s now on a 2-for-33 slide. … Also struggling is Brandon Hicks, who struck out three times and has 18 strikeouts in 33 at-bats.