Social media users have been expressing their astonishment at Dwayne Johnson's 'unrecognisable' look during a film festival.

On Monday (1 September), the 53-year-old Moana actor was honored with a 15-minute standing ovation at the Venice Film Festival for his upcoming sports drama film, The Smashing Machine, which is scheduled to premiere in cinemas next month (3 October).

In videos now circulating on social media, Johnson, also famed as the WWE wrestler 'The Rock', warmly embraced the film’s director, Benny Safdie, while his co-star, Emily Blunt, stood smiling beside him.

For this film, Johnson underwent a significant transformation to portray MMA fighter and UFC pioneer Mark Kerr, a two-time UFC Heavyweight Tournament Champion, World Vale Tudo Championship tournament winner, and a Pride FC competitor.

To resemble Kerr more closely, Johnson used facial prosthetics and reportedly lost around 60 pounds to bring his weight closer to 240 lbs, down from his usual 300 lbs.

Dwayne 'The Rock' Johnson has reportedly lost 60 pounds for his role in the upcoming sports drama, The Smashing Man (Gisela Schober/Getty Images)

"I’m at a stage in my career where I want to challenge myself in ways I haven’t before. I aspire to create films that matter, exploring humanity, struggle, and pain," he stated last year.

Johnson added: "Benny strives to create stories that are raw and real, with characters that are authentic and sometimes uncomfortable and arresting."

The significant weight loss has since ignited a lively online debate, with some critics questioning: "What happened to The Rock?"

"From Rock to Pebble!" joked another, while many others engaged in baseless speculation about his weight loss, unaware it was for a movie role.

However, the majority were quick to defend the Fast and Furious star, with one person writing: "This was him last night as they celebrated a 15-minute standing ovation for his new movie in Venice.

Johnson also wore facial prosthetics to look more like MMA fighter and UFC pioneer, Mark Kerr (A24)

"He still looks massive. Why the hate? Jealousy is an unattractive trait. Why do we need to bring people down?"

"People really don’t grasp the dedication and effort required for big builds," explained another. "As you age, you just want to enjoy life without spending it consuming 6000 calories, meal preps, and endless hours at the gym."

A third added: "The Rock is approaching 60. Maintaining that size wasn't physically feasible. Dave [Bautista] did the same. Kudos to them for choosing healthier lifestyles."

A fourth person remarked: "Why is body positivity only a one-way street? Why is it acceptable for people to speak so negatively about someone like The Rock transitioning from a bulked-up version of himself to something healthier that suits HIM!"