For one night at least since their last breakup, Selena Gomez looked smitten by her ex-boyfriend, Justin Bieber, who serenaded her with a little Temptations.

A fan video caught Bieber singing the classic, "My Girl," to Gomez at the Montage Beverly Hills hotel on Friday night. The poorly lit video shows Bieber from the back while someone off screen accompanies him on piano.

Gomez can be seen at the start of the video sitting with her head tilted to the side as she watches her ex sing to her. He later tickled the ivories himself, playing and singing a stripped down version of his song, "Sorry," off his new album, "Purpose."

The former couple has shared an on-again, off-again romance for nearly five years and most recently broke up in October 2014. Bieber has opened up recently about their rocky relationship, revealing in one interview that they moved in together much too soon and their personal identities were tied too close to one another.

Both Bieber and Gomez will be in attendance at the American Music Awards on Sunday at the Microsoft Theater in Los Angeles. The "What Do You Mean" singer is scheduled to close out the show with a medley of his hit songs and Gomez will also perform earlier in the night.

Watch Bieber's impromptu performance for his ex-girlfriend below:

@justinbieber singing my girl to @selenagomez....is this real? Pure magic. A video posted by lındsey (@eatprayphoto) on Nov 20, 2015 at 9:17pm PST

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