Friends Director's First Impressions of the Cast: Who Was 'Not the Funniest'? Who Became 'Most Improved'?

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Prolific Friends director James Burrows has some insights on the stars of the beloved comedy in the era before they became household names.

In an excerpt of his upcoming memoir Directed by James Burrows shared with WSJ. Magazine, the 10-time Emmy winner opened up about bringing the iconic show to life and discussed some of his gut instincts about its eventual stars.

Burrows, 81, was brought in to direct the pilot of David Crane and Marta Kauffman's sitcom Six of One, which would become the Must-See TV hit.

"I had a good sense about Friends and knew two things immediately: one, I didn't have time to direct it, and two, I had to direct it. It became the last pilot shot that year," he wrote.

He continued, "I fell in love with these six kids on the page immediately. Ninety-five percent of the original pilot script made it to air."

Burrows said they had "amazing luck" in that all six actors they wanted for the show were available.

RELATED: How the Friends Cast Has Stayed Close for 25 Years: 'They Have Really Leaned on Each Other'

The show found its heart in Courteney Cox, even though Burrows wrote the actress initially "was not the funniest one in the group but grew into it and found her humor."

He noted that the series could have easily been called "Monica's friends" because of her role on the show.

"She was stunningly beautiful and was the connection between the other cast members," he wrote.

Chris Haston/NBCU Photo Bank/NBCUniversal via Getty Images via Getty (L-R) David Schwimmer, Matt LeBlanc, James Burrows, Jennifer Aniston, Courteney Cox and Lisa Kudrow

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Jennifer Aniston (or "JA," as Burrow calls her) was "the hardest type to find in comedy — she is both beautiful and funny," according to the director

Burrows gave particular credit to Matt LeBlanc for how he was able to evolve the role of Joey alongside the writers, calling him "the most improved player."

"It's a tribute to his skills that his character developed over the course of the series. He never played Joey as the dumb guy, just as the incorrect guy, the 'much smarter than you think' guy, the one with the most growth potential, the least number of rules, and who became the most empathetic," said Burrows.

He added, "A character can't evolve if it's not in the script, but you also need an actor who can really show that growth. ... He grew the most, because he paid attention to all the notes and was the most willing to learn from the other five and from everyone else involved."

Rodin Eckenroth/FilmMagic

With David Schwimmer, Burrows writes, their relationship grew beyond and director and actor relationship but he also became a mentor to the then-budding director.

"During the first season of Friends, he asked me if I would mentor him. He shadowed me, first on Friends and later on Will & Grace and other sets. I was as happy to teach him as he was eager to learn," Burrows recalled. "He went on to direct 10 episodes of Friends, other television episodes, a few movies and lots of theater in both Chicago and New York. I once told him, 'Schwimmer, you're the second-funniest person I've ever known.' To this day, I've never told him who the first is."

RELATED: Courteney Cox Says Matthew Perry Put 'a Lot of Pressure on Himself' During Friends

Matthew Perry had what Burrows' called a "very distinctive style," saying the actor was the "smart, quick one" on the show.

"He brought the self-deprecating and the funny, good-looking guy to the table," he said.

And though Burrows calls Lisa Kudrow a "really good friend" now, he said he remembers hearing from someone on the show that the actress — who'd just lost the role of Roz in Frasier to Peri Gilpin — said, "'That f---ing Jimmy Burrows is directing the show. Can you believe it?'"

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All six of the show's cast members reunited in May 2021 for HBO's Friends: The Reunion, where they revisited the sets and divulged stories about their time filming the classic sitcom.

"I was flooded with 10 years of irreplaceable memories," Cox told PEOPLE at the time.

Added LeBlanc, "It's funny, when we do get together, it's like no time has passed. We pick up right where we left off."

Directed by James Burrows hits shelves on June 7.