Selena Gomez was joined onstage by her boyfriend Justin Bieber last night (24.07.11).

The 17-year-old pop superstar surprised fans as he took to the stage with the 19-year-old singer as she was doing a gig at the Pacific Amphitheatre in Costa Mesa, California - and he even showed off his musical talents by performing a rendition of Justin Timberlake's 'Cry Me a River', a video on reveals.

After the concert, Justin wrote on twitter: "Had a #greatnight and surprised the people. felt good to be on stage. nothing is changing that. #REAL. @selenagomez u did great tonight. proud of u. (sic)"

He appeared to go down well with Selena's fans, however the 'Wizards of Waverly Place' actress has not always got on with the 'Baby' hitmaker's supporters.

When recently asked how she deals with criticism from Justin's followers, Selena replied: "I just focus on everything that's going on with my fans [instead].

"I thought I was going to marry Jesse Mccartney when I was younger - he was my screensaver. And I've been obsessed with Shia LaBeouf since I was 15."

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