Center Morgan Frost and defenseman Cam York, two of the Flyers’ top prospects, are making progress with the Lehigh Valley Phantoms but aren’t ready to be recalled by the NHL team.

That’s the assessment made by Brent Flahr, a Flyers assistant general manager who keeps close tabs on the team’s prospects.

The Flyers have holes in their lineup because of injuries to second-line center Kevin Hayes and top-pairing defenseman Ryan Ellis. Frost and York, however, need more AHL seasoning, Flahr said Monday.

Frost, 22, has been more productive in recent games, and he leads the Phantoms in points (15) and assists (12) through 16 games.

“He is finally starting to go a little bit,” Flahr said. “Obviously, he’s talented.”

Frost did not have a good training camp and was sent down to the Phantoms. Going into camp, he hadn’t played in nearly nine months because of shoulder surgery.

“You could see he wasn’t ready after missing basically a whole year,” Flahr said. “He was good in the rookie camp, but then when we got him into the exhibition games and going against the Bruins and the rest, you could just see the rust. Things that come naturally to him weren’t natural, as far as handling the puck, making plays, and playing at top speed. And playing with pace is the biggest thing we’re trying to stress.”

Frost was the Flyers’ first-round draft pick in 2017, 27th overall.

“He’s got the great hands and he can make cute plays, but you don’t have time and space at the NHL level to be able to make those plays unless you move your feet and play fast,” Flahr said. “That’s the biggest challenge for him right now.”

Flahr likes what he has seen from Frost recently, “but it’s a work in progress. He measures himself on points — I think any offensive player does — and obviously, a lot of the media and fans do, too,” Flahr said. “And that’s fine, but, unfortunately, in order to play at the NHL level, a lot of the details are where his game needs to improve.”

Besides centering the No. 1 line, Frost has been used on the top power-play and penalty-killing units.

“In the NHL, he may not be on the power play all the time. That’s just the reality, so you have to find other ways to contribute,” Flahr said. “He’s working on the PK, he’s working on faceoffs, he’s working on defensive habits and things like that, which he’s going to have to do against NHL players [someday].

“I think where he is right now is good, and when he’s scoring points, fans are like, ‘Why isn’t he coming up?’ I think putting him on a yo-yo” — going back and forth from the AHL to the NHL — “is not what we want to do. We just want to make sure when he is ready and everything is good, then we can call him up and he’ll probably be done with the American League.”

In The Inquirer’s latest list of the Flyers’ best prospects, York was ranked No. 1 and Frost was No. 3. Wade Allison, who is close to returning from an ankle injury was No. 2.

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York, 20, a first-round selection in 2019 (14th overall), has been playing a lot of minutes for the injury-depleted Phantoms. Like Frost, he has been used in all situations. “He’s learning the pace” of the pro game, Flahr said.

“He’s so smooth with the puck moving up ice, and he’s learning little things like getting back to pucks quicker,” Flahr said. “He’s got to get stronger, but he’s come along.”

Asked if he saw Frost or York joining the Flyers in a month or so, Flahr said: “I don’t think there’s any rush. These guys are so important to our future, and you have to make sure you’re doing it right. The last thing you want to do with these guys is put them on yo-yos. Every time you do that, it really hurts them in the long term.

“You may have a couple good games, and you read about how good you are, and then all of a sudden, your play falls off, and it takes a month-and-a-half or two months to get them back [to playing well] when they get sent back down again.”

Both prospects are “learning and are in a good spot,” Flahr said.

He acknowledged injuries could cause earlier-than-desired call-ups, but for now, Flahr and the front office would rather have players like defenseman Nick Seeler and forward Max Willman play with the Flyers until York and Frost “are really ready.”

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