's Chris Martin
and Jonny Buckland
pose backstage at the iHeartRadio Music Festival
on Friday (September 23) at the MGM Grand Garden Arena in Las Vegas.
The British rockers treated the crowd to a performance during the two-day concert event, which sold out in just 10 minutes when tickets went on sale in July.
Also hitting the stage: Alicia Keys
belting out some tunes with rapper Jay-Z
Couldn't make the iHeartRadio ...