The Islanders’ goaltending situation will be monitored all season by new coach Barry Trotz. So far, Thomas Greiss has gotten the looks.

After Greiss stopped 45 shots in the season-opening overtime win in Carolina on Thursday, he was able to stop only 19 of 23 shots against the Predators in a 4-3, home-opening loss Saturday night at Barclays Center in Brooklyn.

“It was an awkward game, they didn’t shoot it too much,” Greiss said. “They had a couple good chances, a couple good screens, and I couldn’t find the puck.”

Maybe the most glaring goal allowed was the shot from Mattias Ekholm from the top of the left circle that managed to sneak under Greiss’ glove and give Nashville a 2-1 lead at 16:56 of the first period.

“It was a weird knuckle-puck,” Greiss said, “and I just missed it.”

Sitting on the bench and likely to get the start in Monday’s Columbus Day matinee against the Sharks is Robin Lehner, who signed a one-year, $1.5 million deal. Lehner had previously been open about his battle with mental health and substance-abuse issues, and Trotz had a long conversation with him on the ice at Saturday’s morning skate.

“Like anybody else that’s not going through what he’s going through, you say you understand, but you really don’t,” Trotz siad. “So that’s what we were talking about, and that’s what I’m trying to get better at, too, because it’s necessary for me to understand and help the organization.

“He’s gotten all the support in the world from us and we’ll have his back for anything we can do, and he wants to have our back. That’s part of being a good teammate and all those things that go on like that. I think he’s conscious of where he’s trying to get to and he wants to make sure no one is reading into anything.”

Jan Kovar, who signed a one-year, $2 million deal as a free agent this summer coming-out of the KHL, did not report to AHL Bridgeport after his designation earlier in the week. The 28-year-old Czech center is said to be considering his future.

Veteran center Valterri Vilppula scored his second goal in as many games as an Islander. The goal came 2:46 into the second period, a deflection of a Luca Sbisa point shot that was originally credited to Tanner Fritz.

The lineup was the same for the second straight game, with forwards Tom Kuhnhackl and Ross Johnston, along with defenseman Scott Mayfield as healthy scratches.