Fans who have waited nearly 30 years for some form of the Grateful Dead to return to New Orleans must wait a little longer.

Dead & Company guitarist John Mayer was rushed to a New Orleans hospital early Tuesday for an emergency appendectomy, forcing the band to postpone a concert scheduled for that night at the Smoothie King Center.

Concert promoter Live Nation Entertainment has not released information about when the show will be rescheduled. Previously purchased tickets will be honored on the rescheduled date. Refunds are available at the point of purchase.

Dead & Company performed in Austin on Saturday. After the now-postponed New Orleans concert, only two dates remain on its fall tour schedule: Thursday in Orlando and Friday in Sunrise, Florida. As of Tuesday afternoon, the band had not released any information on the status of those shows.

Mayer headlined his own concert at the Smoothie King Center in August, sporting a T-shirt that referenced the Grateful Dead song "Box of Rain." At 40, he is the youngest member of Dead & Company. His bandmates include three holdovers from the Grateful Dead's classic lineup — guitarist/vocalist Bob Weir and drummers Mickey Hart and Bill Kreutzmann — plus bassist Oteil Burbridge and keyboardist Jeff Chimenti.

They began touring as Dead & Company following the Grateful Dead's Fare Thee Well farewell concerts in 2015. 

The Tuesday night show at the Smoothie King Center would have been a rare New Orleans appearance by either the Grateful Dead or one of its direct descendants.

On Jan. 30-31, 1970, the Grateful Dead shared a bill with Fleetwood Mac and the Flock during the opening weekend of the Warehouse, the legendary brick concert hall on Tchoupitoulas Street.

Following the first of the two scheduled shows, 19 members of the Grateful Dead entourage were arrested on drug charges at the Bourbon Street hotel where they were staying. The incident inspired the “busted down on Bourbon Street” lyric in the song “Truckin’.”

The musicians were released on bail in time to perform the second show at the Warehouse. They and Fleetwood Mac also performed on Feb. 1 for a hastily arranged “Bread for the Dead” benefit to raise money for the band’s legal fees.

The Grateful Dead finally returned a decade after the bust for a two-night stand at the Saenger Theatre on Oct. 18-19, 1980, playing both acoustic and electric sets. The second night's show included the first and apparently only performance of "Truckin' " in the city that inspired its most famous verse.

They returned to the Saenger again on Sept. 9, 1982. On Oct. 18, 1988, they made their debut at the UNO Lakefront Arena, a year after the single “Touch of Grey” became an unexpected MTV hit. Members of the pop band the Bangles — who had opened for George Michael at the Superdome earlier that night — and the Neville Brothers joined the Grateful Dead onstage for the final encore of “Knockin’ on Heaven’s Door.”

Given Mayer's medical emergency, the long, strange trip that is the Grateful Dead's history in New Orleans has taken another curious twist.

Follow Keith Spera on Twitter, @KeithSpera.

Keith Spera writes about music, culture and his kids.