GRAMMY winner Justin Timberlake is no stranger to the GRAMMY stage. In fact, he's graced the stage seven times in his career so far, including performances with Arturo Sandoval, the Black Eyed Peas, Robyn, Jay Z, and T.I.. But what's his favorite GRAMMY moment? The time he performed alongside "the Reverend" Al Green with Boyz II Men and Keith Urban at the 51st GRAMMY Awards.

This supergroup of performers took on Green's classic hit "Let's Stay Together" but, according to Timberlake, the performance was a last minute-ensemble cobbled together by GRAMMY telecast producer Ken Ehrlich. 

Timberlake recounts how Ehrlich kept trying to get a hold of Green to confirm his telecast performance. While Green ultimately came through to help deliver this incredible GRAMMY moment, it turns out he was otherwise occupied when he got the phone calls.

"I picture that [Green's] taking this fantastic bubble bath and he gets the phone call and someone walks in and they say, 'Reverend, the GRAMMYs needs you,'" says Timberlake. "For me, it was one of the greatest moments I've ever had at the GRAMMYs."

Watch Timberlake and other artists reminisce about the most memorable performances in GRAMMY history on the upcoming TV special "GRAMMY Greatest Stories: A 60th Anniversary Special," airing Friday, Nov. 24 from 9–11 p.m. ET/PT on CBS.

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