Cameron Diaz has called Justin Timberlake a 'genius comedian'
The pair, who dated for three years, team up for new comedy Bad Teacher and Diaz reveals that the singer turned actor was the best person for the job.
Speaking to People the actress said: "Justin and I have always had a good laugh together, and to make a movie where we get to have a laugh together...
"There really was no-one else who was more perfect for this part. That's why he got the part.
"He's a genius comedian, everybody knows. Saturday Night Live and all the stuff that he's done over the years, he's clearly talented.
"We went for the best person for the job, and it just so happened that it was him. And he delivers."
Bad teacher is the second movie of the year for the actress having already starred in Green Hornet.
Directed by Jake Kasdan the movie also Lucy Punch and Jason Segel.
Bad Teacher is released 24th June.
Tagged in Cameron Diaz Justin Timberlake