Brian Cashman said the Yankees had “concerns” about the Astros before Houston was found to have used an electronic sign-stealing scheme and the general manager added his team did what it could to stop the scheme’s effectiveness.

“We’ve done our due diligence,’’ Cashman said Thursday night on YES Network’s “Yankees Hot Stove” in his first public comments since MLB commissioner Rob Manfred released his report about the scandal that has dominated the offseason.

“We tried to do everything we could — and have done everything we can — to protect our signs as much as possible and continue to evolve over the course of time because of concerns,’’ Cashman said.

MLB investigated after former Astros pitcher Mike Fiers said Houston was using a video camera to steal signs. Manfred suspended Houston manager A.J. Hinch and GM Jeff Luhnow for the year and fined the team $5 million while also stripping the Astros of their next two first- and second-round picks. Hinch and Luhnow were then fired by Astros owner Jim Crane.

“Baseball has now determined, with the strong assistance of Mike Fiers coming forward, being a whistle-blower, and shed a light on some of the things that were occurring down in Houston, clearly,’’ Cashman said.

Cashman added he hadn’t addressed the situation with his team since the ruling, noting that they haven’t been together since the close of last season, which ended for the second time in three years at the hands of the Astros in the playoffs.

He also said the Yankees were waiting to see what comes out of MLB’s ongoing investigation into potential electronic sign-stealing by Boston in 2018, when former Houston bench coach Alex Cora was the manager of the Red Sox.

Aaron Boone, who didn’t manage the Yankees in 2017, but was there in 2018 when the Astros were still found to have been stealing signs, called the findings “disappointing [and] frustrating.’’

“But in the end, you hope these are significant steps — and I believe that they are — that will get us to a point where we have a much cleaner and more fair game between the lines,’’ Boone said on YES. “I think for a long time, teams guarded against the unknown. … Hopefully, we’ve put an end to this and cut it off, finally.’’

Cashman, at the GM meetings in November, expressed frustration over the situation.

“I don’t think it’s a technological question alone. It’s just conduct,” Cashman said. “You decide to play by the rules, or you don’t. And if you don’t, there’s consequences.’

Cashman said Thursday he hopes his team will look forward, not back.

“I think everyone is focused on the individual jobs at hand,’’ he said. “When the dust settles, we’ll have further conversations. But the healthy thing to do now is to focus on the future and try not to look back too much.”

Cashman also admitted the Yankees’ injury-plagued 2019 season “forced us to do a deep dive into an area we thought was taken care of.”

That resulted in the firing of strength and conditioning coach Matt Krause and the addition of Eric Cressey as director of player health and performance.