First came Barry Trotz being hired as the Islanders head coach on June 21. Just over a month later, team president Lou Lamoriello brought in up-and-coming goalie coach Piero Greco from the Toronto Marlies. The next day, the team announced Trotz’s longtime goalie whisperer, Mitch Korn, had been hired as the director of goaltending.

What’s that say concerning how the organization’s new leadership felt about what happened between the pipes the prior season?

With the addition of Robin Lehner to share the duties with Thomas Greiss, and with Trotz instilling a defensive system that made things exponentially easier on the netminders, the turnaround has been nothing short of remarkable. Lehner and Greiss had two of the best goaltending regular seasons in Islanders history, as the team went from having the fourth-worst collective save percentage in 2017-18 to the best. They went from last in goals against to first, the first team to do that in 100 years.

And now goaltending is an absolute strength as they prepare for their first-round playoff series against the Penguins, starting with Game 1 on Wednesday night at the Coliseum.

“What I like with them, and where I had problems before, they haven’t come in and said to me, ‘I have to change,’ ” Lehner said of his new position coaches. “They’ve changed a few things, but they haven’t really tried to change my game that much. They’ve been trying to help me develop my game, and not change me from the goalie that I am. Fix some fundamental stuff and work on some fundamental stuff. It’s been good so far.”

Lehner has been a great bounce-back story all season, a shoo-in for the Masterton Trophy after dealing with substance abuse and mental health issues. He is likely to start Game 1, but it sure seemed like Trotz was planning on using both goalies as he sees fit.

“Honestly, I can’t make a bad decision,” he said following Monday’s practice. “And I’m going to use goaltenders in this series, so don’t ask me who’s going to start.”

Coming into training camp, Greiss was also trying to put his career back on the rails after a disastrous season. As the Islanders were the worst defensive team in the league under head coach Doug Weight, Greiss had the third-worst save percentage (.892) in the league for goalies with over 25 games played.

Yet, just as it was with Lehner, the new goalie coaches didn’t try to completely overhaul Greiss’ game. There were only a few small adjustments, things the deadpan Greiss joked were “goalie secrets.”

“I think both goalie coaches [have helped],” he said seriously. “Obviously work together very tightly and have good working relationships, and talk about everything, It’s not like I’m a totally different goalie now, just little things, some regular adjustments. And happy it has worked out so far.”

Both Greiss and Lehner will have their names etched on the Jennings Trophy, given to the goaltender(s) who played at least 25 games for the team that finishes the regular season with the fewest goals against. But they are considering it a team award, which is certainly true to some extent.

“Our goalie department has done a terrific job with them, in Piero and Mitch. And I think they’re very comfortable,” Trotz said. “Obviously, we’ve been consistent to make it predictable for them.”

Lehner, 27, became one of the best signings of the summer, inked to a one-year, $1.5 million deal. It should be interesting to see if the Islanders try to lock him up to a longer-term deal or let him test the market. Greiss, 33, is in the second year of a three-year, $10 million deal that is now looking more reasonable.

So with the help of two new coaches — three, including Trotz — the Islanders goaltending is once against a strength. The club is hoping however Trotz decides to play them, it can help propel the team to just its second postseason series victory since 1993.

“I think it comes down to our whole team thing,” Greiss said. “Great coaching, great goalie coaching. It’s a great team together.”