During Usher's performance at the iHeartRadio Music Festival on Friday night, Sept. 19, Chris Brown joined the singer and dancer on stage in Las Vegas to perform their collaborative hit, 'New Flame.'

'New Flame,' which also includes rapper Rick Ross on the album version, was released on June 30 as a single. The song is Brown's fifth single off his recently released sixth studio album titled 'X.'

At its peak, the song has reached number 36 on the Billboard Hot 100.

Chris Brown's 'X' was finally released on Sept. 12 after several delays. ‘X’ was originally slated for release on July 16, 2013. That date was then pushed to November, and then later to December of 2013. But after Brown was sentenced to anger management, and then later to jail, the album was put on hold until his release.

Click on the video above to check out Chris Brown & Usher performing 'New Flame.'

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