As the old adage goes, when one door closes, another opens.

This was apparently the case for Brad Pitt during his struggling actor days, going on to fame and fortune after losing out on a guest-starring role in “Cheers”, then one of TV’s most popular sitcoms.

In an interview with Entertainment Weekly, veteran Hollywood casting agent Jeff Greenberg reveals the reasos Pitt didn’t land the role: he wasn’t funny.

“My only note was ‘Not funny,’” Greenberg recalls, but adds a caveat: “For the part, he wasn’t funny — he’s been funny since.”

Greenberg’s extensive resume includes casting such TV series as “Frasier”, “My So-Called Life”, “Ugly Betty” and “Modern Family”, among others, and divulges his philosophy when it comes to finding the right person for a role. “I try to find the actor who enhances what’s on the page, who not only fulfills the vision of the writer, but brings a dash more — someone who is fresh,” he says. “And always have a backup plan, always have someone in the wings, just in case.”

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Sometimes an actor or actress has the right stuff but, at the time of auditioning, may simply not be ready. That was the case when he passed on young Keri Russell (whose screen credits included the “All New Mickey Mouse Club”) when she auditioned for “My So-Called Life”. “But in my casting notes, I wrote, ‘Star to be,’” he adds. “I tracked her career and observed what was inevitable. It was that apparent.”

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Casting Call: Stars Nab A New Role

In addition, Greenberg says he’s managed to help several stars on their journey to the top, revealing he recommended Meg Ryan for the role of Goose’s wife in “Top Gun”, which proved to be her breakout role.

“I actually knew Meg’s work from an episode of ‘Charles in Charge’,” he says. “She came in and grabbed her big break.”

Greenberg can also take responsibility for the success of Eric Stonestreet, casting him in “Modern Family” after auditioning him for numerous other projects.

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“He had been auditioning for me for 10 years,” says Greenberg of Stonestreet. “I remained a fan, and he was always good. We had a very hard time casting that part, and Eric created the alchemy the role needed by finding the funny and grounding it with his mother’s spirit, so that the mix of the masculine and feminine sides of the role were entwined.”

Perhaps the most challenging series he ever worked on was the short-lived Seth Green sitcom “Four Kings”, which led him to audition 637 actresses (including the likes of Jessica Chastain, Busy Philipps and Krysten Ritter) for the role that ultimately went to Kiele Sanchez. Meanwhile, he also auditioned 336 actors for the show’s four primary male roles, including Channing Tatum, Max Greenfield, Sebastian Stan and Zach Gilford, along with future co-stars Neil Patrick Harris, Jason Segel and Josh Radnor. “’How I Met Your Mother’ was casting at the same time,” he recalls, “and wisely plucked all three.”

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Actors That Nearly Nabbed The Big Role