Kevin Long hadn’t met Brandon Marsh before Thursday. But he was already well-acquainted with his swing.

In the frenzied hours before the Phillies acquired Marsh in a deadline trade with the Los Angeles Angels, they asked Long to check out video of the 24-year-old center fielder. Then, once the deal went through, the Phillies hitting coach really dove in.

“I went back to 2017, so it was quite a few hours,” Long said. “There’s a lot to digest and go through.”

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No matter what you think of the Phillies’ moves — short-term pickups of veteran reliever David Robertson from the Chicago Cubs and right-hander Noah Syndergaard from the Angels, and longer-term plays for Marsh and infielder Edmundo Sosa from the St. Louis Cardinals — Marsh’s future will most determine whether it was a successful deadline. Because center field has been a wasteland for the Phillies, and they wagered with catching prospect Logan O’Hoppe that Marsh can turn it into fertile ground.

Defensively, there isn’t much doubt. Marsh made his major league debut a few days after the All-Star break last season. Since then, he has saved three runs more than the average outfielder and recorded 10 outs above average, according to data from Sports Info Solutions. For those who don’t trust defensive metrics, the good old eye test bears it out, too. He covers center field like a tarpaulin and has a rocket-launcher arm.

And if that’s all Marsh does for the Phillies over the next two months, specifically catch everything that gets hit between Kyle Schwarber and Nick Castellanos in left and right field, he will have aided in the here-and-now pursuit of ending the National League’s longest postseason absence (10 years, in case you hadn’t heard).

But if the Phillies cared about only defense in center field, they could have worked out a deal for Brett Phillips or Jackie Bradley Jr., cut loose this week by Tampa Bay and Boston, respectively. They were looking for more upside, so they kicked the tires on several young, controllable center fielders, including Arizona’s Alek Thomas and Houston’s José Siri.

The Phillies landed on Marsh, even though he has struck out in 35.6% of his major league plate appearances and batted .178 with 86 strikeouts against breaking pitches. They agreed to essentially a straight-up prospect-for-prospect swap for O’Hoppe because they believe Marsh is far from a finished product as a hitter.

They aren’t alone in that view. Since the trade became official Tuesday, talent evaluators from rival teams have weighed in with mostly favorable opinions that are rooted in speculative gambles that Marsh will hit.

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Why? As one scout noted, Marsh lost a year of development in 2020 because the minor league season got wiped out by the pandemic. As another pointed out, the 2016 second-round pick has fewer at-bats as a professional (1,765 between the minor leagues and the majors) than even Mickey Moniak (2,190), the 2016 No. 1 overall pick by the Phillies who coincidentally is the Angels’ replacement for Marsh after getting traded for Syndergaard.

“Good move by Dave [Dombrowski] to get Marsh,” one National League scout said. “I am a believer.”

Said another NL evaluator: “Everyone likes his athleticism. Others like him a little more on the projection to hit. But both [camps] think he’s an everyday guy.”

Marsh’s self-evaluation of his offense: “There’s definitely more to give.”

This is where Long comes in. The Phillies hired him after last season because they believe in his long-standing reputation as a hitter whisperer. And he had a plan for Marsh even before Marsh walked through the doors to the clubhouse.

After studying video of Marsh’s at-bats dating to rookie ball in 2017, Long decided to widen his stance to get him to use his legs more. They talked about eliminating Marsh’s stride to improve his timing. In batting practice Thursday, Long, Marsh, and Jean Segura talked about how Segura has seen the benefits of a shorter stride.

Long believes Marsh’s struggles stem more from his setup and stance than his swing. If Marsh is able to simplify his movements, it may improve his timing. He’s hitting .238 and slugging .357 with a 27.9% whiff rate against fastballs compared with .318, .432, and 24.1% last season, a sign that he’s late to pitches.

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“He’s got some moving parts that kind of get in the way of him being consistent,” Long said. “That’s it. It’s nothing more, nothing less, but it’s going to lead to trouble with off-speed and swing-and-miss on some fastballs that he should be able to hit.”

Marsh made a positive first impression. In his Phillies debut Thursday night, he broke his bat and looped a single into left field on a curveball from Washington’s Paolo Espino. He made a good first-to-third read on Schwarber’s single to center field, then scored easily on Rhys Hoskins’ single to left field.

“That swing is going to come along,” Bryce Harper said before the game. “It did for him in the minor leagues. And once he gets to play every single day, work with Kevin Long, I think he’s going to be really good for us.”

Marsh’s impressions of Long so far?

“Amazing,” he said after their first hitting session together. “Explored some things, found out some stuff about me that I had no idea about. It’s just timing, being on time for the heater, reacting to the off-speed.”

OK, pump the brakes.

The Angels tried to help Marsh over the years, too. In 2018, in the midst of a protracted slump after he got moved up to high A, they changed his bat path to spur more contact. It worked for a while, but he still wound up striking out 158 times in 580 plate appearances (27.2%). In 2019, they got him to stand more upright in the batter’s box to try to unlock his power. He slugged .545 in the final 29 games of the season at double A, but hasn’t developed into a big home run threat.

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It’s fair to wonder about the pandemic’s effect on Marsh and other players in his age and experience bracket. He would have moved up to triple A in 2020 but instead settled for simulated games at the Angels’ alternate training site. He played only 24 triple-A games last season before getting called up and struggled almost immediately.

Marsh got off to a good start this season. But his downturn paralleled the Angels’ team-wide collapse. He batted .204/.258/.318 in his last 77 games, and with the Angels eyeing O’Hoppe, they decided to cash in Marsh.

“Brandon’s close to my heart after spending this much time with him,” said Angels first-base coach Damon Mashore, who worked closely with Marsh in the minor leagues. “But it’s a great opportunity. I’m happy for Brandon to get a fresh start. There’s going to be stuff that he learns there that maybe didn’t make sense or wasn’t making sense here.

“He’s going to grow. I can’t wait to see what he does.”

The Phillies can’t either, especially after a wave of top prospects (Adam Haseley, Scott Kingery, Roman Quinn, and Moniak) couldn’t unseat wildly inconsistent Odúbel Herrera for years in center field.

But they’re also trying to play the long game. Marsh isn’t eligible for arbitration until after the 2024 season. He can’t be a free agent until after the 2027 season. That’s a long runway for him to take hold of center field, as the Phillies believe he will.

“Listen,” Long said, “I’m not expecting miracles overnight. The way I look at it, we’ve got through the end of September — because I plan on playing in October, and so do these guys — to kind of get it right. The sooner it comes, the better it is for him and our team.”

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