Co-founding guitarist Tom Johnston is off the Doobie Brothers‘ 50th anniversary tour in order to undergo back surgery. Johnston, who’ll miss the band’s upcoming leg, is taking leave per his doctor’s orders while recovering from the surgery to alleviate the “severe back pain” he’s been enduring.

The band — led by co-founder Pat SimmonsMichael McDonald, and John McFee — will kick off the band’s next leg on May 25th at Hollywood, Florida’s Hard Rock Live.

Tom Johnston said in a statement:

I hope for a speedy recovery and can’t wait to get back on the road and continue doing what I love. I would like to thank Pat, Michael, John, and the entire Doobie Brothers band for covering for me while I recover from back surgery. I’m sure they will bring it every night as they always do.

Patrick Simmons, the sole member to have survived the numerous lineup changes, admits life as a Doobie Brother has pretty much been a dream come true. We asked him if he ever expected the Doobies to still be played constantly on the radio and out gigging at sold out shows to a die-hard legion of fans after all these years: “Not in a million years (laughs). Y’know, most bands, y’know, last a year or two and — if they’re lucky. For me to have been able to record and make music with all these great, great players — and still be doing it — it’s just ridiculous (laughs) — I’m not worthy, y’know? For me, y’know, being a part of a band like this is has always been sort of; I felt, a gift (laughs). Not just musically, but the whole opportunity to kind of like the dream, in terms of being able to pursue something that you love to do and make a living out of it.” SOUND