WHILE Chris Hemsworth’s career has skyrocketed since being cast as Thor, The Avengers co-writer, Zak Penn, has revealed that the iconic God of Thunder almost took a huge hit.

In an interview with The Hollywood Reporter, an honest Penn admitted that he had his doubts about how well the comic book character would translate on to the big screen.

While Penn was in the process of writing the first script for the Avengers, Thor and Captain America: The First Avenger were still in the development phase.

“Originally I was trying to reduce how much Thor was in the movie. Once it was clear that, no, this is going to work and they were excited about it, then I did not [reduce Thor in the script]. I stopped doing that,” Penn told The Hollywood Reporter.

Kenneth Branagh, director of the first Thor instalment, also admitted to being under extreme pressure to make the franchise a success.

Despite being hesitant about the franchises’ success, Penn believed that Hemsworth’s casting was a masterstroke for Marvel Studios.

One that helped to solidify the presence of Thor in The Avengers.

“I remember Chris Hemsworth walking through the Marvel offices, and being, ‘Oh, my god, that guy IS Thor,’” Penn said.

It is difficult to imagine how the Marvel Cinematic Universe would look today, if Thor had not received the treatment that it did.

What’s more, the success of Thor inspired Marvel Studios to launch the cosmic side of its universe with Guardians of the Galaxy in 2014.

Guardians later went on to receive two Oscar nominations.

Although the casting of Hemsworth as Thor has been praised, the movies themselves have been met with a mixed reception.

While the first instalment mostly received positive criticism, the sequel Thor: The Dark World, is considered by many to be one of the worst Marvel movies to date.

However, New Zealand director Taika Waititi lifted the series to new heights when he took the helm of Thor: Ragnarok.

The third instalment has been the biggest success of the series, earning a worldwide total of $US854 million.

The shift from a dark and somber tone to a comedic, dry Kiwi one was extremely well received.

Sadly, for fans of the big guy, Hemsworth’s contract with Marvel will expire following the release of Avengers 4 in 2019.

Time will tell whether he will resume the role and lift his hammer once more.