Fans still can't believe that Jerry Stiller has been gone for more than a year. The man was a force of nature. A comedic genius. Unquestionably beloved. A singular talent. And everyone who worked with him knew this. Perhaps no one more so than his famous son, Ben Stiller, who continuously grieves his father's death while recalling some truly happy moments. But Jerry made an impact on far more than just his son and fans of his work. The man also endeared himself to the cast of Seinfeld. But that almost wouldn't have happened since Jerry wasn't the first choice to play Frank Costanza.

It's hard to imagine anyone else bringing to life the temperamental, creative, and downright strange father of George Costanza. Jerry's performance was just so specific and perfect for the character. Over the course of filming his 27 episodes of Seinfeld, Jerry developed one of the show's most iconic supporting characters. This reminded the show's creators, Jerry Seinfeld and Larry David, that they made the right choice by casting him. But there was a time when Jerry almost didn't play Frank. In fact, they were happy to hire and work with another actor.

John Randolph Played Frank Costanza Before Jerry Stiller Was Hired

In season four of Seinfeld, audiences were finally introduced to Goerge Costanza's father. Up until that point, he had only been talked about. Estelle Harris had already appeared as Goerge's mom, Estelle Costanza. But Jerry and Larry needed a Frank.

"I couldn't image who they were going to get for my husband," Estelle Harris said in the behind-the-scenes documentary for the episode "The Handicap Spot". "And then I found out that it was John Randolph. A darling, sweet, wonderful man and a marvelous actor."

When the character of Frank Costanza was originally conceived, he was supposed to be a far more docile character. Estelle was supposed to "wear the pants" in the relationship. Her character was extremely dominant so they required an actor to play a far more subdued character. So, acclaimed theater legend John Randolph was hired.

"John Randolph and I had worked together on Broadway, he had played my grandfather in Neil Simon's 'Broadway Bound'," Jason Alexander explained. While Jason said that he loved working with John, he didn't think he "looked like a Costanza".

Eventually, something clicked with the writers and the character of Frank was developed further and John had to be replaced. This was fairly easy given that John had only done the one episode of Seinfeld.

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How Jerry Stiller Got The Part Of Frank Costanza

"The following season, I don't know if John wasn't available or something about... something made us want to change the actor," Larry David explained. "[Director] Larry Charles suggested Jerry Stiller and um... and he was great and we loved him. And then, because of [the show going into] syndication, they would keep re-running 'The Handicap Spot' with John Randolph and it would seem odd that George would have two different fathers. So, I prevailed upon Castle Rock and NBC to let me re-shoot those scenes with John Randolph and replace them with Jerry Stiller which is what we did."

The same thing happened with the original actor who played Jerry's father, but Larry decided not to go and re-shoot that due to it being in the very first season and the characters aging so drastically. The choice to only replace John Randolph wasn't a personal one, it just made more sense for the show and the character that Frank ultimately became. Even Jerry Stiller had immense respect for John as he was one of the people who inspired him to become an actor. John even gave Jerry advice after the two met in John's dressing room after a Broadway performance.

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While Jerry was extremely grateful for his experience on Seinfeld, he did feel bad about replacing John. This is because the two became friendly and John was actually blacklisted in Hollywood for potential ties to the Communist Party. When he did finally come back, Jerry replaced him.

"I had very mixed feelings, but not for long," Jerry Stiller admitted. This is because Jerry really needed to work at the time. His Broadway show had just closed and he needed the money. According to an interview with The Television Academy, Jerry flew out and had a great meeting with Larry David. But he wasn't thrilled with the character at first.

At the time, Larry and the writers still wanted Frank to be weaker than Estelle. Jerry wasn't happy about this nor liked his lines. He even tried to change them but NBC told him not to. Come the rehearsals for the show, Jerry tried yelling back at Estelle in the scene and everyone started laughing. In that moment, the real Frank Costanza was born. Larry, Jerry, and the rest of the team decided to let Jerry play with the character and ultimately develop him into just as much of a force as his wife.

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