Mets’ David Peterson implodes in ugly first postseason blemish

LOS ANGELES — Kodai Senga exited a disappointing start in which there was little mystery what went wrong: He could not find the plate.

David Peterson entered shortly after and pitched in a similarly disappointing fashion that bore few other similarities: Peterson found the plate but also found Dodgers bats, hit for the first time this postseason.

The Mets’ Plan A failed before the Mets’ Plan B did not encourage in a 9-0, NLCS-opening loss at Dodger Stadium on Sunday night .

Peterson, one of the Mets’ most valuable players through October in beginning the postseason with 6 ¹/₃ scoreless innings in relief, looked more mortal against the Dodgers than he did against the Brewers and Phillies.

He was not exactly crushed but was dinged in an outing he called a “mixed bag.”

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“I felt good with my stuff. Felt good health-wise,” said Peterson, who allowed three runs (two earned) on four hits and a walk over 2 ¹/₃ innings against perhaps baseball’s best lineup. “I just didn’t get the ball to [Shohei] Ohtani where I wanted to on the curveball.”

All of the damage against Peterson came in a fourth inning in which the Dodgers turned four singles — including a very long one from Ohtani — a sacrifice and a Starling Marte error into a three-run frame that blew the game open.

In the inning, righty hitter Kiké Hernandez lined a changeup the opposite way, into right, and moved to second on a bunt from Gavin Lux.

Righty-hitting Tommy Edman went the same way, taking a Peterson fastball into right to score a run.

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Peterson then left a curveball over the heart of the plate to Ohtani, which is not advisable: Ohtani blasted it 116.5 mph off the bat and off the wall in right-center.

Marte dropped the carom off the wall, which mattered when Edman slid in safely just ahead of the relay throw.

“Left it up,” Peterson said of the pitch to Ohtani, “and good hitters are going to do what he did.”

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Mookie Betts grounded out hard before lefty-swinging Met-killer Freddie Freeman drove an outside sinker for a third opposite-field single of the inning, dumping a hit into left field.

Brandon Nimmo’s throw home was too late to catch a sliding Ohtani.

“Felt like Freddie took what I gave him and did what he could do with it,” Peterson said. “And then I felt like I executed some good pitches. Felt like the changeup to Hernandez was good, and he just kind of shot it the other way.”

Peterson was happy with the Mets’ game plan, but the Dodgers’ go-the-other-way approach might have beaten him in the inning.

Peterson settled from there but pitched only through the fifth in a 40-pitch outing that will mean he is not available for Monday’s game and also likely not stretched out enough for a lengthy start in Game 5, if the Mets decide to pivot away from Senga.

“Hopefully [Peterson is] back available for Game 3 if we need it — we’ve got to get to Game 3 and Game 4 and we’ve got to make a decision, but he’s too valuable for us,” manager Carlos Mendoza said. “We’ll see what kind of shape we’re in bullpen-wise, and then we’ll have to make decisions and see how Senga’s feeling, too.”

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