Could a reunion of the classic Guns N' Roses lineup take place in the next two years? Craig Duswalt, Axl Rose's personal manager from the group's 'Use Your Illusion' tour, believes it could happen.

These comments come on the heels of the release of Duswalt's memoir, 'Welcome To My Jungle.' Seeing as how the time he spent with the group included the last time the original line-up toured together, he is intimately familiar with the relationships among the former bandmates.

Duswalt tells ABC News Radio that he believes that Duff McKagan's return to the band to occasionally fill in for current Guns N' Roses bassist Tommy Stinson's commitments to the Replacements is the catalyst which will eventually reunite the original lineup.

McKagan most recently appeared with Guns N' Roses in Las Vegas, and he also performed with the group at several shows in South America. "Duff is paving the way to open the gates again," Duswalt says. "Axl and Duff are really getting along well at the concerts, so there's an opening."

Despite the current good vibes between Rose and McKagan, Duswalt acknowledges the most fractured relationship is the one between Rose and guitarist Slash. Mending that bridge is going to be the ultimate deciding factor. For what it's worth, Slash does not believe that Rose will be calling him any time soon.

"About five years ago, Slash went to Axl's house one day, and Axl didn't want to see him. We [had] thought for a while yes [a reunion could happen], but then it just got ugly again and we thought, 'There's no way.'"

Duswalt elaborates further on the acrimony between Rose and Slash, acknowledging that he knows "for a fact they hate each other right now. It's bad. Axl is a loyal guy and you get on his bad side and some people don't come back, but Slash and him were so close. We [in the old-school Guns camp] all have a feeling it will happen. It's gonna happen in the next two years...there's an opening because of Duff playing with Axl."

For the past two decades, many have wondered exactly what precipitated the nasty split between Rose and Slash. And though Duswalt does not mention the specific incident that caused the chasm between the two, musical differences and the direction of the band played a part:

"It was a thing that happened at the end of ['Use Your Illusion']. There were also the differences in music. Slash wanted to do more hard rock stuff and Axl wanted to do more ballads, rock ballads. There was that difference, but there was [also] a specific thing that happened that both of them are at odds over."

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