He once represented 60 NFL first round draft picks, including eight #1 overall selections, and seven Hall of Famers. Steinberg was also the inspiration for the hit movie Jerry Maguire, and still hears the quote, "Show me the money!" on a daily basis.
But after Steinberg hit a series of unfortunate events, including a divorce and the death of his father, Steinberg became an alcoholic.
"I felt powerless and I turned to the wrong thing," he said. "I turned to alcohol and spun downwards."
Steinberg eventually lost everything and had to file for bankruptcy. He even ended up moving in with his mother. But four years ago, Steinberg began to turn his life around.
"In 2010, I made a decision that if nothing else, I'd be a sober person and a good father," Steinberg said. "So I'm now in my fifth year of sobriety."
Once the most powerful sports agent in the world, representing such high profile athletes as Troy Aikman, Steve Young, Warren Moon, Ben Roethlisberger and Oscar De La Hoya, Steinberg has resurrected his career.
Now he is more involved in sports movies, television shows, video games, apps, and continues to encourage his clients to stay heavily involved in charities. Thursday night he spoke at the Eye Care 4 Kids charity in Salt Lake City, which has raised 75,000 pairs of eyeglasses for lower income kids.
"I saw where athletes could be role models and trigger imitative behavior," said Steinberg, who says he and his clients have helped raise roughly $800 million for various charities over the years. "They've got a real ability to change behavior for the better. Steve [Young] was charitable to begin with, and he had those impulses. You rarely meet a young man that's quite that bright and quite that perceptive."
Along with trying to get sports stadiums to go green, Steinberg has also been on a crusade to stop concussions in football.
"I became really concerned and had a crisis of conscience back in the 80's because I was representing players that were getting hit in the head," he said. "The doctors had no answers at the time. So we need urgently to be doing research into a new helmet that does more than just protect against skull fractures. We need better diagnostic techniques on the sidelines. We're talking about consciousness, memory, character and what it means to be a sentient human being."
From encouraging his clients to become role models, to now inspiring people himself, Leigh Steinberg has written the ultimate comeback story.
"The message to anybody who's out there hopeless and in the grip of some substance is there is help for you," he said. "You can get your life back."