Mathew Barzal will be paired with Pierre Engvall and Bo Horvat on Islanders' top line

In training camp, Mathew Barzal mused aloud about the possibility of Pierre Engvall skating alongside him and Bo Horvat.

Now, 4 1⁄2 months and one coaching change later, Barzal’s idea is going to be tested.

The only question: for how long?

“I don’t have a timeline,” coach Patrick Roy said after Monday’s practice at Northwell Health Ice Center during which Engvall skated with Barzal and Horvat on the Islanders’ top line.

The trio likely will be together to start Tuesday night’s game against the Seattle Kraken at UBS Arena. Anders Lee will skate with Brock Nelson and Kyle Palmieri on the second line.

Why?

“I want to see different [line combinations]. See how things will go. It could be short-term. It could be long-term,” Roy said. “It could be two [shifts] in the first period and I go back to [Lee on the top line and Engvall on the second line], but right now I’m curious to see those lines.”

That’s likely due in part to what the analytics have shown. According to data culled by NaturalStatTrick.com, Barzal leads the Islanders in Corsi For percentage (.5253) and is second on the team in Fenwick For percentage (.5403) and Shots For percentage (.5498). Horvat is second in Corsi For (.5249) and first in Fenwick For (.5403) and Shots For (.5422). Engvall is fourth in Corsi For (.5074) and fifth in Fenwick For (.5107) and Shots For (.5163).

Theoretically, creating a line with three of the team’s top five puck possession players could increase the amount of time the Islanders spend in the attacking zone.

Roy made the decision to swap Engvall and Lee early in the third period of Saturday’s 5-2 loss to the Flames at UBS in an attempt to generate offense. The Islanders outshot Calgary 17-3 in the period and scored two goals.

“We definitely had some good shifts at the end of the last game,” Barzal said. “[Engvall] was gaining puck possession [and he] moves his feet, so I hope we go out and score a couple goals.”

Along with bringing another puck-possession element to the line, Engvall adds a speed component that complements Barzal and Horvat.

“If we’re using the speed and .  .  . we play the right way, play hard, I think [scoring chances] are going to come,” Engvall said.

Still, the great unknown is if or when the three Islanders will develop chemistry. According to Moneypuck.com, over the entirety of the season, Engvall, Horvat and Lee have skated together for 14.8 minutes spanning 22 games.

“A lot of [it will be] us just talking, communicating, knowing where each other is [going] to be out there,” Horvat said. “That’s just by talking and getting used to each other. So it’s not going to happen overnight, but we’ll get that opportunity tomorrow. Just make the most of it.”

Isles files

Roy said defenseman Alexander Romanov (lower-body injury) is “day-to-day” but “looked good” during practice, and a team spokesperson said Hudson Fasching (lower-body injury) has started skating on his own.