LOS ANGELES — Ignore Mets left-hander Sean Manaea’s history against the Dodgers. The 32-year-old is no longer the pitcher with a 7.09 ERA in 11 career matchups (eight starts). A new arm slot has made Manaea a force to be reckoned with (a 2.98 ERA since July 25) and more confident than ever.

The Mets need this version of Manaea to send the National League Championship Series to Queens even at one game apiece when he starts Game 2 on Monday afternoon, on the heels of a 9-0 loss to the Dodgers in Game 1 at Dodger Stadium.

“Just trying to do my best to go out there and just give the boys a chance to win,” Manaea said, “and this opportunity is no different.”

Manaea’s first order of business will be keeping NL Most Valuable Player favorite Shohei Ohtani — who has 16 hits in his past 19 at-bats with runners in scoring position — in check.

Ohtani went 2-for-4 with a walk, an RBI and two runs in the NLCS opener. After grounding out in the first against right-hander Kodai Senga, he got payback with an RBI single in the second. Ohtani barreled the ball in his next two at-bats — a 116.5 mph single off lefty David Peterson in the fourth and a 103.1 mph, 394-foot flyout to center against southpaw Danny Young in the sixth.

“I felt good with my stuff, felt good health-wise, and just didn’t get the ball to Ohtani where I wanted to on the curveball and left it up,” Peterson said. “Good hitters are going to do what he did. We’ll clean that up, clean the execution up, and a couple other pitches that I would have liked to execute a little better. But we’ll learn from them, and we’ll move on.”

Due to Senga’s abbreviated start (1 1/3 innings), the Mets needed to use four relievers, including both of their southpaws, Peterson (2 1/3 innings, 40 pitches) and Danny Young (1 1/3 innings, 18 pitches). This makes planning for Ohtani a bit tricky for Game 2.

Mets manager Carlos Mendoza elected to go with Peterson rather than righty Tylor Megill as the bulk arm because the Dodgers’ lineup featured four left-handed batters and a switch-hitter. With the Mets trailing 3-0 in the second inning, Mendoza hoped Peterson could keep it a close ballgame for the offense to rally like it has all season.

Instead, Peterson allowed three runs (two earned), as Los Angeles extended its lead to six by the fourth. By going this route, Peterson will not be available for Game 2, leaving New York with just two lefties — Manaea and Young — to try to neutralize Ohtani on Monday. Then there’s the matter of whether the Mets would replace Senga with Peterson, who made 21 regular-season starts, for a possible Game 5 on Friday at Citi Field.

“Hopefully he’s back available for Game 3 if we need — 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,” Mendoza said of Peterson. “But again, 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.”

Why is it so important for the Mets to have southpaws available to face Ohtani? Here are his splits:

• Slash line: .322/.411/.717 (482 PA) vs. RHP; .288/.349/.518 (249 PA) vs. LHP
• Homers: 42 vs. RHP; 12 vs. LHP
• Strikeout percentage: 21.6 vs. RHP; 23.3 vs. LHP

Without Peterson, this could force Mendoza into leaving Manaea in to face Ohtani for a third time, a risky move for opposing teams since Ohtani’s slash line was .395/.442/.798 with 12 homers in those instances.

Despite being American League West rivals for a few seasons with the A’s and Angels, respectively, Manaea and Ohtani have squared off just nine times. Ohtani is 2-for-7 with two walks and no extra-base hits.

Otherwise, expect the 30-year-old rookie Young to be called upon in a key situation, or even closer Edwin Díaz if need be.

“I pride myself on being available no matter what,” Young said. “I would have thrown 35 pitches today. I would have come in and said, ‘I’m available.’ I’m always available. I treat it as such. That’s how I’ve come into the last six, seven games that I didn’t play in [the] same way. So pitching one, I expect to pitch in the next, and the next, and the next, and the next. And at this point here, I’m happy to do that.”