Jacob deGrom left his start on Tuesday night with back...

Jacob deGrom left his start on Tuesday night with back stiffness. Credit: Jim McIsaac

Back tightness limited Mets ace Jacob deGrom to just one inning in an intrasquad game Tuesday night.

In what was scheduled to be his second-to-last outing before Opening Day, deGrom’s throwing regimen suggested he should have pitched much longer. He tossed three innings in his previous scrimmage start, which would have put him in line for four or so Tuesday.

The Mets did not provide any further detail on deGrom’s status.

His night ended suddenly. In the first inning, he gave up a single to Amed Rosario and struck out Brandon Nimmo and J.D. Davis. But at the start of the second, lefthander Justin Wilson entered and the position players loitered as Wilson made extra warm-up throws.

Behind deGrom, the two-time defending NL Cy Young Award winner, in the rotation are Marcus Stroman, Steven Matz, Rick Porcello and Michael Wacha.

The Mets’ depth starter options include Corey Oswalt and Walker Lockett on the 40-man roster, as well as non-roster pitchers Erasmo Ramirez and David Peterson.

Scrimmage scribblings

Also in the Mets’ instrasquad game, Dominic Smith homered off of Corey Oswalt.

This scrimmage came with a greater degree of reality. They played at 7 p.m. under the stadium lights, as opposed to their recent mid-afternoon starts, and had real umpires making calls. The Citi Field PA system played players’ walk-up music, too.

When relievers — including Wilson, Edwin Diaz and Dellin Betances — entered, the Mets placed speedy outfielder Johneshwy Fargas at second base. That was meant to practice the new extra-innings rule that puts a runner at second to begin every half-inning.

Extra bases

The Mets assigned 11 players (eight pitchers) to their alternate training site in Brooklyn on Tuesday. Manager Luis Rojas said they still might come to Citi Field for workouts and they are still competing for roster spots…All of the Mets’ starting pitchers are expected to be built up to 85-100 pitches — normal early-season range — by Opening Day…Porcello with a little perspective: “We’re in a global crisis, there’s civil unrest in our country and things are very difficult. So for us, being at the ballpark and having the privilege and the opportunity to be able to get some relief from that and play a game every day is exciting. Hopefully in a couple of weeks we can provide the rest of the country with a release from these tough times.”

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