John Mayer's health took a turn for the worse Tuesday, as he was rushed into emergency surgery.
The singer-songwriter was supposed to be headlining a New Orleans concert with Grateful Dead offshoot Dead & Company this evening, but he's been sidelined to have an appendectomy.
Dead & Company tweeted: "Early this morning, John Mayer was admitted into the hospital for emergency appendectomy forcing the Dead & Company December 5th concert in New Orleans to be postponed.
"All tickets for the December 5 show will be honored for the rescheduled date. Information on the rescheduled date will be announced as soon as possible. Should ticketholders choose to seek a refund, they will be available at point of purchase."
Dead & Company are on the verge of wrapping up their autumn concert tour, with only two more dates scheduled for Orlando, Florida on Thursday and Sunrise, Florida on Friday.
It remains to be seen if those concerts will be postponed as well, but both dates are currently still listed as going ahead on Dead & Company's touring page.
Mayer has spent most of this year focusing on his solo work, having released comeback album The Search for Everything and single "Still Feel Like Your Man" this past spring.
The 40-year-old Connecticut native also recently made headlines for confirming that some of the music on The Search for Everything was inspired his on-off relationship with ex-girlfriend Katy Perry.