"I just talked to Roger and he can barely speak," guitarist Pete Townshend reportedly told the crowd a few minutes later. "I tried to get him to come out here, but he's really, really sick." Townshend promised the audience that the band would reschedule the show for a March 25 make-up date.

On Wednesday (3/14), Townshend will gave the keynote address at the SXSW music festival in Austin, TX; he is scheduled to perform some shows with his partner, Rachel Fuller, while he's there.

Meanwhile, The Who is scheduled to resume performing Saturday (3/17) in Mexico City, assuming Daltrey's condition improves. Only a few dates remain on the band's tour, which kicked off last September.

The group is backing its latest album, "Endless Wire." Released last October, the disc is The Who's first new studio set since 1982's "It's Hard." The album includes several brand new tracks, as well as music culled from a 29-minute mini-opera inspired by Townshend's novella "The Boy Who Heard Music." The book is available online at Townshend's website.

As previously reported, surviving group founders Townshend (guitar) and Daltrey (vocals) are now backed by drummer Zak Starkey (son of Beatles drummer Ringo Starr), guitarist/vocalist Simon Townshend (Pete's younger brother), bassist Pino Palladino and keyboardist John "Rabbit" Bundrick.