Williams appeared on stage Monday for the "Triple Guitars Night" at Feinstein's at Loews Regency in New York, joining noted musicians John Pizzarelli and Earl Klugh to raise funds for Ed Randall's Bat For The Cure charity and its fight against prostate cancer.
"It's a great thing, especially for me," Williams told MLB.com. "I grew up listening to Earl Klugh and John. When I was up in the clubhouse playing my guitar, instead of listening to rock and blues, I was listening to those guys play.
"It's definitely a dream come true for me to be here and just enjoy the time, especially when it's for such a great cause like this."
While Williams promised that it would be a fun night for all in attendance, joking that he just hoped to keep up with the likes of Klugh and Pizzarelli, his best personal moments may have come before the lights went on.
Williams is an accomplished guitarist in his own right, having already released two jazz-influenced albums -- "The Journey Within" in 2003 and "Moving Forward" in '09, the latter of which was nominated for a Latin Grammy.
But the author of 2,336 hits in a Yankees uniform was entirely happy to play the role of spectator during the sound check. As the musicians warmed up, Williams watched from the side of the stage, trying to soak in as much of the experience as possible.
"To me, it was just like a master class," Williams said. "Eric has some tunes that he wanted the band to go through at sound check, and I was just checking his technique, his chord changes and the whole interaction with the band.
"When I started feeling comfortable playing a note here and a note there, it was like being in a master class. That's probably one of the things I will remember most about this night, just being there when nobody was in the crowd. It was just me and those two great guitar players."
Bat For The Cure is a New York-based charity entering its ninth year of raising prostate cancer awareness, promoting early PSA testing and raising research funds to fight the disease.
The charity has held free prostate cancer screenings at Yankee Stadium, Tropicana Field and U.S. Cellular Field, and is also an official charitable partner of Minor League Baseball.
"I know for Bernie, Earl and John, as well as our great supporter John Iachetti of Feinstein's at Loews Regency, our goal is the same: helping men stay healthy through greater awareness and knowledge about prostate cancer," Randall said.
Williams said that it was important to champion the cause of prostate cancer, with 240,000 new cases expected in the United States this year, making prostate cancer the leading cause of cancer deaths.
Yet through early detection, prostate cancer is almost 97 percent treatable, and Williams said that it is vital that men remember to make the trip to their physicians for examinations.
"It's an organization that on and off I've been around, listening to Ed all the time talk about it," Williams said. "He's been a champion for that cause. Even when I was playing, we were always aware of the fact that we needed to create awareness of that situation.
"Even after my playing days are over, I'm here making sure that I don't forget to give back to the community. What more fun way to do that than doing something like this?"
Bryan Hoch is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.