Grateful Dead, John Mayer Stage Free Concert: Where, Where & Other Details Here

Let the mad scramble for tickets begin.

Bob Weir, Billy Kreutzmann, and Mickey Hart of the Grateful Dead and John Mayer will be staging a free concert November 7 at New York's Madison Square Garden.

"The musicians, who are touring this fall under the name Dead and Company, will add a third show on Nov. 7 to their Garden stand and give away 10,000 tickets through a sweepstakes," Mashable said. "The contest will allow fans to support the Robin Hood Foundation, a New York-based group devoted to fighting poverty."

The show is backed by American Express, Vevo, and YouTube. Live footage of the event will be streamed via the Unstaged app and amexunstaged.com on the night of November 7 - welcome news for fans who won't be able to score tickets.

To join the sweepstakes, fans need to enter the Dead & Company website. None of the tickets will be sold.

Whisperings of the band's collaboration with Mayer began earlier this year, in the wake of the announcement of The Grateful Dead's reunion shows.

"A fall tour featuring John Mayer is in the works. According to insiders, the trek is due to kick off in October, with the Grammy-winning singer and guitarist having already begun to jam in a rehearsal-like setting with select members of the group, chief among them Weir," Billboard reported in April this year. "Observers say he's ecstatic about the prospect."

And now, it appears the rumor was spot on, as the artists officially announced in August that the remaining members of the band and Mayer will be forming supergroup Dead & Company, with Allman Brothers bassist Oteil Burbridge and Ratdog keyboardist Jeff Chimenti completing the lineup, Rolling Stone said.

The group will start its fall tour October 29 in Albany, New York, according to Yahoo! News.

"We're about halfway in and rehearsals are going well, if I may say," Weir shared. "We've been through 45 or 50 tunes and I'm not going to tell you that we have them entirely locked down, but we have a good handle on them."

Grateful Dead had formally split in July after holding three big shows in Chicago.

"Those songs weren't done with us. It was a matter of who wanted to get back out on the road and keep doing it," Weir said of their decision to join forces once more, also saying that Mayer's enthusiasm to work with the band made the prospect a "good idea."

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