The singer/actor stars alongside Woody Harrelson, Mila Kunis and Emma Stone in the new romantic comedy and the two male stars had to shoot part of their storyline on a basketball court in New York.
Paparazzi snapped Timberlake in action and one shot shows him dunking the ball through the net.
But the SexyBack hitmaker, who stands at six feet, one inch (1.85 metres) tall, confesses he isn’t as good as the image suggests.
He says, “I think they lowered it (the ring) to about eight or nine (feet). I can jump, but I can’t jump that high.”