Justin Timberlake and Ben Affleck are reportedly lined up to star in gambling thriller ‘Runner, Runner’.According to The Hollywood Reporter, Timberlake’s casting is confirmed while Affleck is in final negotiations.The thriller, which centres on the world of online gambling, will be directed by Brad Furman (The Lincoln Lawyer), with a script by Ocean’s Thirteen writers Brian Koppelman and David Levien.Leonardo DiCaprio is a producer on the movie, with filming to begin in Puerto Rico this summer.