MANCHESTER, TennesseeMumford & Sons have canceled their headlining performance at the 2013 Bonnaroo Music and Arts Festival. The announcement comes following the hospitalization of their bassist, Ted Dwane, this week to remove a blood clot on his brain.

The band wrote Thursday night on its Facebook page, "It is with sadness that we have to announce the cancellation of our scheduled performances at both Bonnaroo and Telluride Festivals ... If we could've we would've, you know that about us. We trust that you can respect our collective desire to encourage Ted to make a full recovery, and that this is based purely on the medical advice we have received."

The band also reported that Dwane has been discharged from the hospital and his medical team is "very pleased" with his recovery.

No word yet on who will replace Mumford & Sons, who were scheduled for a two-hour set on the main stage Saturday night.

The guys remained lighthearted in their announcement, joking, "[Dwane] has been nothing short of heroic in how he has handled the whole ordeal, and now it has been medically proved that he does indeed have a brain."

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Also dropping off the roster is Odd Future's Earl Sweatshirt. The rapper told fans on Thursday that he was too ill to perform, writing, "To everyone at Bonnaroo: I'm sorry I can't make it, I'm really really f---ing sick but I will make it up to Tennessee as soon as I possibly can."

After some fans seemingly took issue, Earl followed that up with some more detail on what is ailing him. "To everyone who think I'm being overdramatic, go get pneumonia and then try singing 'Whoa' all the way through with no hypeman. I'm just sayin."

Twenty One Pilots kicked off the festival Thursday, drawing a big opening-day crowd for their late-afternoon set, as cloud cover and a cool breeze offered welcome relief from the Tennessee heat. A huge mass of thunderstorms moving east across this part of the country barely brushed Manchester, leaving only one brief downpour Thursday afternoon. That should be it for rain on the farm this year: The next front isn't expected to move through until Monday.

Who should replace Mumford &Sons as the Saturday night headliner at Bonnaroo 2013? Share your ideas in the comments section below!