All-Star outfielder Brandon Marsh relegated to platoon role (for now) as the Phillies seek more production against lefty pitching

Brandon Marsh started the All-Star Game last week.

Now, he’s longer starting every day for the Phillies.

Marsh wasn’t in the lineup Saturday night against the Yankees, the second time this week that he sat out against a left-handed starting pitcher. It could be an uncomfortable situation, so interim manager Don Mattingly met with Marsh to explain his reasoning.

“Honestly,” Mattingly said, “you have to look at the numbers at some point.”

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And these are Marsh’s numbers against lefties: .233 batting average, .645 OPS.

So, Marsh insists he will do what he’s done for most of his career and set aside his ego for a manager who wants to play the matchups. In this case, it meant staying ready to replace righty-hitting Edmundo Sosa in left field or Bryan De La Cruz in right once the Yankees lifted lefty starter Ryan Weathers.

“The way I look at it is I’m a baseball player, and I play for Don Mattingly and for the Phillies,” Marsh said. “I’ve got nothing but love and respect for him. I’ll ride for him. I’ll die for him. And if he wants De La [Cruz] to go run out there and take the nod in left field, then that’s what’s going to happen. And I hope De La Cruz hits three homers tonight.”

It’s imperfect to run three platoons in the outfield. But for now, and unless the Phillies acquire a righty-hitting upgrade before the Aug. 3 trade deadline, Mattingly seems intent on mixing and matching.

Against righties, Marsh will play left field, with rookies Justin Crawford in center and Gabriel Rincones Jr. in right. Against lefties, Mattingly is using Sosa in left, Derek Hill in center, and De La Cruz in right.

Clearly, though, there’s room for an upgrade. Entering the weekend, the Phillies had a .302 on-base percentage against left-handed pitching, tied for 26th in the majors. Collectively, their right-handed hitters were reaching base at a majors-worst .276 clip.

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If the Phillies can add a right-handed bat, they may be better able to tolerate Marsh’s struggles against lefties.

“I do believe that he’s going to be a guy that can be an everyday guy,” Mattingly said. “Something we talked about is understanding how to hit lefties and what you need to do. Understanding ball movement, what do you want to hit, where does [the swing] have to start. He’s a guy that, honestly, at the big league level has really not had the opportunity to continue to do that.

“But at some point, we’re trying to win games. We need to be better against lefties. Again, I do feel like he’s going to be that guy that could play every day, but right now, it’s just not showing up in the numbers.”

Marsh was showing some improvement against lefties early in the season. Through June 25, he was 21-for-77 (.273) and slugging .429. Since then, he’s 3-for-26 (.115) and slugging .231.

In the ninth inning Tuesday night, he huddled with Kyle Schwarber before facing Dodgers lefty Tanner Scott. He wound up cueing a ball to third base, which led to a game-ending double play after bad baserunning by J.T. Realmuto.

But Schwarber, who had little success against lefties earlier in his career, has been a resource for Marsh, who said he has gained a better understanding for how lefties want to attack him.

“He’s able to relate to players like me, guys who are following his footsteps,” Marsh said. “He can tell us everything that’s going on in his head to help us out.”

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It hasn’t translated into better overall numbers, but Marsh said he’s confident that his approach against lefties is improving.

“I feel more comfortable against them for sure, just with the reps that I’ve gotten this year and the work we do in the cage and stuff like that,” he said. “Definitely a lot more room for improvement. Really just got to keep the head down and grind, but definitely a lot better than years prior.”

For now, though, it seems he’ll be watching most lefty starters from the bench.

Although injured reliever Brad Keller will fly to Texas on Monday for a second opinion from orthopedic surgeon Keith Meister, Tommy John surgery remains the likeliest outcome.

The Phillies will continue to seek a late-inning reliever before the deadline to replace Keller.

In the meantime, Kyle Backhus was recalled from triple A to give Mattingly another lefty in the bullpen against the Yankees and next week in Miami and Baltimore. Hard-throwing Alex McFarlane and fellow righty Max Lazar were optioned to triple A for Backhus and righty Brian Keller, called up to make his major league debut after an opener on Saturday night.

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The Phillies placed lefty reliever Tanner Banks (forearm strain) on the 60-day injured list to clear a 40-man roster spot for Brian Keller. … The Phillies acquired lefty-hitting outfielder Kam Misner from the Royals for cash and optioned him to triple A. Misner, 28, is a .206 hitter with five homers in 253 major league at-bats. Switch-hitting outfielder Steward Berroa was designated for assignment to get Misner on the 40-man roster. … Mikal Bridges, NBA champion with the New York Knicks and notable Phillies fan, was on the field and in the clubhouse before the game. … Cristopher Sánchez (12-4, 2.71 ERA) is scheduled to start the series finale on Sunday Night Baseball against Yankees righty Will Warren (7-4, 4.00).