A new biography of Walter Payton details the Hall of Fame running back's frequent drug use, extramarital affairs and the crippling loneliness that plagued him after his retirement from the NFL.

Sports Illustrated's Jeff Pearlman spent more than two years working on "Sweetness: The Enigmatic Life of Walter Payton" and uncovered startling details about the Chicago Bears running back who was so highly regarded that the NFL named its Man of the Year Award after him.

The book is set for release next week. Excerpts appear in this week's Sports Illustrated. In one section, Pearlman describes Payton's drug use:

The burden of loneliness and his marriage weren't Payton's only problems. As a player he had numbed his maladies with pills and liquids, usually supplied by the Bears. Payton popped Darvon robotically during his playing days—says Holmes, "I'd see him walk out of the locker room with jars of painkillers, and he'd eat them like they were a snack"—and also lathered his body with dimethyl sulfoxide, a topical analgesic commonly used to treat horses. Now that he was retired, the self-medicating only intensified. Payton habitually ingested a cocktail of Tylenol and Vicodin. In a particularly embarrassing episode, in 1988, Payton visited a handful of dental offices, complaining of severe tooth pain. He received several prescriptions for morphine and hit up a handful of drugstores to have them filled. When one of the pharmacists noticed the activity, he contacted the police, who arrived at Payton's house and discussed the situation.

Pearlman also details Payton's use of the painkiller Darvon during his playing days and how he equipped an RV with nitrous oxide to use during training camp.

Once Payton's career ended, he battled depression and often discussed suicide with close friends. Two failing relationships contributed to his malaise. Pearlman describes how Payton's estranged wife and girlfriend both attended his Hall of Fame induction ceremony -- "they were like ships passing in the night," Payton's assistant said -- and made the triumphant weekend one of the worst of Payton's life.

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Like Andre Agassi's recent autobiography, in which he detailed his previously unknown drug use, "Sweetness" will be most remembered for the salacious tales revealed within. They'll dominate discussion over the next few days and obscure the brighter stories included in the book: How Payton delighted a cancer-ridden youngster on a flight or those moments when he'd play catch with kids before signing their football. The drug use and affairs will make some forget about how graceful Payton was on the field and how strong he was when facing terminal illness, and how he grew up in segregated Mississippi and calmed racial tensions there with his on-field heroics.

As "Sweetness" shows, our heroes are always more complex than we know.

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