Legendary British rock group The Who have begun the US leg of their first world tour in 20 years with a concert in Philadelphia.
The Who are hoping to finish the tour with a gig at Glastonbury
The band, who first shot to fame in 1965 with songs such as I Can't Explain and My Generation, played a two-hour set at the city's Wachovia Center.
Along with their most famous hits, the gig featured a number of songs from forthcoming album Endless Wire.
The record will be their first new material since 1982's It's Hard.
The group struggled with some of the new songs, and guitarist Pete Townshend apologised to the crowd after a performance of a seven-song "mini-opera" from the album.
"Thank you for putting up with it - I know it's tough to hear new music," he said.
Townshend apologised for the rough sound to some new songs
Townshend and singer Roger Daltrey are the only surviving members of The Who's original line-up.
They have been joined by Townshend's brother Simon on guitar, Pino Palladino on bass and John Bundrick on keyboards, with former Beatle Ringo Starr's son, Zak Starkey, on drums.
Earlier this month they announced 14 new dates would be added to the North American leg of the world tour.