When Justin Bieber and Justin Timberlake met, Bieber sang to Timberlake. Which song?

Explanation

Justin Bieber's manager Scooter was looking for someone to help Justin when they first started their meetings in the studio. "Justin Timberlake or Usher would be perfect", he thought, and he managed to get both to take a look at Justin's YouTube video. Afterwards, both wanted to meet him. Justin Bieber and Justin Timberlake met in Timberlake's house in Memphis. Jessica Biel was also present. Justin sang the number "Cry Me a River" - a brave choice as this is Timberlake's own song. Timberlake wanted to sign Bieber, but he chose Usher in the end.