Chris Squire, a founder of the progressive-rock band Yes and the only member to have played with the British group since its inception, has been diagnosed with a type of leukemia that will prevent him from touring this summer.
"This will be the first time since the band formed in 1968 that Yes will have performed live without me," Squire said in a statement. "But the other guys and myself have agreed that Billy Sherwood will do an excellent job of covering my parts and the show as a whole will deliver the same Yes experience that our fans have come to expect over the years."
Sherwood, who's been friends with Squire since 1989 and was a member of Yes in the late 1990s, said it was "truly a bittersweet moment" when his buddy called with the medical news and asked him to fill in.
"My love for the band and for my friends made the answer very easy," Sherwood said on Facebook. "'of course' I said, 'under the banner of your returning asap', we agreed and so I'm very honored to say that I will be playing bass and singing with Yes on this upcoming Yes/Toto tour."
The 67-year-old bass player has acute erythroid leukemia, an uncommon form of acute myeloid leukemia, the band said on its website. He will undergo treatment for the blood and bone marrow cancer over the next few months in Phoenix, his hometown.
Yes' hits include "I've Seen All Good People" from 1971's "The Yes Album," "Roundabout" and "Long Distance Runaround" from the 1972 album "Fragile," and "Owner of a Lonely Heart" from "90125" in 1983.