LONDON (AP) -- Hong Kong superstar Eason Chan's world tour has an unofficial catch-phrase: "Who the hell is Eason Chan?"
The singer says that was the question a ticket seller asked after he sold out London's O2 Arena in around 20 minutes and crashed the venue's servers.
Millions of fans already know the answer: The 37-year-old has released 30-plus solo albums and is one of the best-selling Mandarin and Cantonese pop artists.
Chan, the first Chinese artist to play at the prestigious arena, says he was surprised at the high demand for Monday night's Duo World Tour concert.
But, Chan told reporters on Sunday: "It doesn't matter what language you sing in, what makes it universal is the energy that you give out."
This is his second appearance on a London stage after performing at the Royal Albert Hall in 2010.