The US Open champion and Olympic gold medallist had lost out in four Grand Slam finals before breaking his duck at Flushing Meadows last month.
And the Scot has now admitted that he turned things around thanks to the intervention of Alexis Castorri, a psychologist based in Florida.
It was the 25-year-old's coach who persuaded him to try out a psychologist, Murray has now revealed - and he suggested Castorri, the woman who helped Lendl surpass John McEnroe to become world number one back in the 1980s.
"When I first spoke to Ivan in December, he asked if I used a sports psychologist," he said.
"I said no. He asked if I was open to it. I said that I was always open to try things, try new people.
"Most times when I'd spoken to sports psychologists before, I ended up talking about the tennis court, what goes on there, ways to deal with the time in between points, all of that stuff.
"There's been a bit of that, but I've spoken a lot more about things off the court, which is completely different."
Murray added that the key thing he has picked up from Castorri is, "learning how to deal with people a little bit better.
"Obviously, I've known a lot of the guys I've worked with for a very long time. We are also friends, so it can sometimes be hard to open up if there's something you're not necessarily happy with, something you want to change. That's probably what's helped most.
"When my mind isn't free of everything, when things might be frustrating me away from the court, I can't focus as well as I need to.
"When my mind's clear, I can go on the court and play, not worry about anything else. I can play much better and think a lot better on the court.
"When I was young, my tactical knowledge, knowing how to win matches, was always one of my best attributes.
"Sometimes if I wasn't thinking about the match, I was wasting one of my biggest assets. I've been able to use that more.
"The US Open was a good example of that. I didn't play my best throughout the tournament, but I played smart tennis. Even when it was really tough, I found ways to win when I wasn't playing well."