David Feherty's brilliance stems from his honesty -- not only about the golfers he covers inside the ropes, but also the transparency with which he shares his personal struggles.

The Irishman, who became an American citizen in 2010, has bipolar disorder and has been sober for 10 years, overcoming almost two decades of alcohol and drug addiction. In an interview with Rolling Stone, Feherty detailed his daily habit, particularly in the late 1980s and '90s.

"A typical day was 30-40 Vicodin and two and a half bottles of whiskey…real whiskey. Whiskey with an 'e,'" Feherty said. "There was cocaine, there was dope. When I think about it now I'm like, 'Why am I alive?'"

Feherty relayed the story of winning the 1986 Scottish Open, then going into Glasgow that night for a concert. He woke up two days later at 2014 Ryder Cup host Gleneagles Resort being poked by former Led Zeppelin road manager Peter Grant, apparently after having made a trip to London and back on a train.

"It's still confusing to this day," he said. "Oh, and the Scottish Open trophy is still lost. God only knows where the hell it is."

However, in 2005, Feherty's life took a turn for the better, in large part thanks to Tom Watson.

"I was doing a TV thing in Canada with Jack Nicklaus and Tom, and at one point, Tom just put his hand over the camera and said, 'You're not well, are you?' and I said, 'No, I'm not,'" Feherty said. "I asked him how he knew, and he said, "I can see it in your eyes." And I said, 'What do you see?' and he said, 'My reflection.'"

Watson told Feherty he should come to his home in Kansas City, while Nicklaus offered to put Feherty on his G5 plane so he could get to Watson's home. Feherty says he's been sober since, thanks as well to his second wife.

In the same year, Feherty began going to therapy and was diagnosed as bipolar, which he said was a "revelation" to him.

Ultimately, Feherty believes it is his unique view of the world that has allowed him to call on golf on TV for going on 20 years.

"For me, I see from a different side of the street than most people," he said. "And I think one of the reasons I got hired to do commentary is the ability to describe something differently."

Ryan Ballengee is a Yahoo Sports contributor. Find him on Facebook and Twitter.

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