John Wetton won't be part of Asia's initial concerts with Journey as he continues to fight cancer. Yes' Billy Sherwood will fill in for Wetton on Asia's March and April dates, which include an appearance on Cruise to the Edge.

"I will soon be starting a new medical chemotherapy procedure, under which I will not be able to fly," Wetton said in an official statement. "While I am naturally disappointed to miss the beginning of what I know will be an historic Asia tour, I am intending to return to the stage with Asia later in 2017 – dates soon to be announced. I know this decision will be in the best interests of my health and our fans in the long run."

Sherwood earlier subbed for an ailing Chris Squire in Yes, before officially taking over when the future Rock and Roll Hall of Fame inductee died following his own cancer battle. Wetton's 2011 solo album, Raised in Captivity, was co-written and produced by Sherwood, whom Wetton describes in the release as a "good friend." Geoff Downes, a member of both Asia and Yes, guested on Raised in Captivity.

The Yes-hosted Cruise to the Edge sets sail on Feb. 11. Kansas and Steve Hackett are among the other featured acts. "I know my friends on the cruise, both artists and fans, will have a ball on the ocean wave," Wetton added. "I will be with you all in spirit."

Wetton co-founded Asia with Downes, Steve Howe and Carl Palmer in the early '80s after stints with King Crimson, Bryan Ferry and Roxy Music, Uriah Heep and Wishbone Ash. Howe has since left Asia to focus exclusively on Yes.

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