Mumford & Sons were forced to cancel the remainder of their Stampede Tour due to bassist Ted Dwane’s emergency surgery to remove a blood clot on his brain, which includes their headlining gig at Bonnaroo on Saturday night. They have since been able to get Jack Johnson to replace them.

Johnson was planning on going to the festival anyway, and he agreed when festival organizers asked him last minute.

"I called my band and asked if they were up for it," Johnson said, Rolling Stone reports. "Long story short – they are headed this way. I've got a lot of lyrics and chords to relearn by Saturday night. I was here to play the first Bonnaroo and it is a very special festival to my band. We are excited to hit the stage again."

Meanwhile, Mumford & Sons updated fans on Dwane’s health, saying he has been discharged from the hospital after a “successful” surgery.

Other dates they had to cancel on doctor’s orders are the upcoming Telluride Festival and a show at the Cricket Wireless Amphitheater.