David Nail, Pat MonahanDavid Nail spent last Friday night on the other side of the stage -- for most of the evening, that is -- watching one of his favorite bands, Train, rock Nashville's Ryman Auditorium. Fresh off of the success of a new smash pop hit, 'Hey, Soul Sister,' the pop-rockers rolled into town on their Save Me San Francisco tour after several years off and proved they're back with a vengeance.

A longtime Train fan, David was both excited and nervous to get the call inviting him on stage for a duet of Train's 'I'm About To Come Alive,' which David also recorded as the title track of his current album. He posted on his Twitter page before the show, "I ain't never been nervous like this, and I ain't one bit scared to admit it! If I needed humbling, it's going down tonight!"

But he rose to the task beautifully, joining Train's lead singer Pat Monahan in a stirring rendition of the aching ballad that had the crowd on its feet. Fittingly, since it was in a church, the show was more like a giant revival at times than merely a concert, with the entire crowd of 2000-plus singing along to every word of hits like 'Calling All Angels,' 'Meet Virginia,' and 'Drops Of Jupiter.'

At one point pausing to pay reverence to the significance of the Ryman, Pat stepped to the front of the stage and launched into the band's hit, 'When I Look To The Sky' without a mic as his voice filled the rafters of the hallowed hall. Audience members couldn't resist singing along even to that song, quietly whispering the lyrics along with him as he absorbed the history of the room into his very performance. Some tiny audience members even got in on the act onstage as Pat later brought several young children up and made them official 'Trainettes,' directing the mini-backup singers on 'She's On Fire.' Bounding back and forth across the stage and engaging the audience at every turn, Pat seemed to have as much fun as the adoring crowd during the phenomenal lovefest of a show.

After the concert David took to his Twitter page again, calling the experience "very surreal and humbling. A huge honor last night singing with Train! What a year it's been thus far!"

Train appeared to enjoy their stop in Music City as well. They tweeted about the show, too, calling it, "A magical night in Nashville last night. Thanks to our friends David Nail and Tony Lopacinsky for sitting in with us."

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