The best-laid plans of starting pitching went south in St. Louis with the Mets besting the Cardinals bullpen in a ten-inning battle.

Zack Wheeler’s wonky outing is cause for concern for manager Mickey Callaway, who’s already dealing with Matt Harvey’s disappointing demotion to the bullpen.

The reconstructed right-hander was rocked for four runs in as many innings, coming off a prior three-run, seven hit performance – putting a strain on the Mets unpredictable starting rotation.

With Steven Matz unable to find his 2015 form, the Mets can’t survive the season on Jacob deGrom and Noah Syndergaard alone. The much-anticipated debut of Jason Vargas will be unveiled in San Diego on Saturday with NY hoping the transplant from Kansas City can repeat last year’s 18 wins as a Royal.

Tuesday night’s come from behind victory was a much-needed boost after a deflating loss to the Braves behind deGrom’s brilliant seven innings of shutout ball.

Consecutive walks by Wilmer Flores and Todd Frazier in the fifth were as good as hits in front of Yoenis Cespedes, who broke out of a 0-13 slide with a 463-foot three-run bomb to knot it up at four.

Cespedes described the mental process he went through in that at-bat.

“He was lost with the fastball and losing the strike zone with it, so I was focusing on catching the changeup and then I caught it.

But Harvey’s premier relief performance helped the Cardinals cause while hurting his own, yielding back-to-back doubles, putting his team at a 5-4 disadvantage.

Adrian Gonzalez bailed out the beleaguered newbie in the bullpen with a sac fly in the eighth, scoring Frazier, who reached first on another free pass, landing on third by way of Bruce’s single to left. The slumping right fielder entered the game batting .194, upping his average to .222 going 3-5, including an RBI triple.

In the tenth inning with two outs, Jay Bruce delivered again in the tenth with a solo home run to win the game.

Bruce talked about how the offense has been clicking after the game, as detailed by Matt Ehalt of The Record.

“We haven’t really been clicking on all cylinders but guys have picked us up and we’ve played very good baseball. That’s an ode to the talent and the depth we have. We have a really long lineup and guys who can carry the load if they need to.”

Aside from Harvey’s hiccup the pen batten down the hatches with Paul Sewald holding down the fort for two frames, Robert Gsellman securing his third win, and Jeurys Familia notching his ninth save.

The bullpen ended up being one of the key factors in this team’s victory. Early on, we have seen just how crucial the success of the bullpen is to this team. The Mets have managed to show the good, the bad, and the ugly already this season. Last night, the Mets were fortunate to get the good side of it.