Kumail Nanjiani knew he'd reached peak physical form for his role in Marvel's Eternals after he was praised by action hero Dwayne Johnson.

The Big Sick star stunned fans last month when he shared two shirtless photos on Instagram, showing off his full body transformation for his role as Kingo in the upcoming comic book adaptation.

The images went viral and in the accompanying caption, Nanjiani explained he'd spent the past year on an intense diet and fitness regimen to achieve his ripped physique.

His dedication to the job won him a flood of compliments from fans and celebrity friends, but there was one person in particular Nanjiani was especially proud to have impressed - former wrestler-turned-actor Johnson.

"Dwayne 'The Rock' Johnson said, 'Dense muscle is hard to achieve, my brother.' He thinks my muscle is dense!" the 41-year-old exclaimed on U.S. talk show Jimmy Kimmel Live!. "How he could see that? If The Rock says it, who knows better?"

However, Nanjiani said having the pictures "explode" online was a weird experience which "really got out of control".
And even his family members were blown away by his new muscular body, which caused a sensation in the star's native Pakistan.

"My brother said, 'Dad already sent your (half) naked pics to both families' WhatsApp groups,'" he recalled. "And then it goes in newspapers in Pakistan. So, I had all my aunts texting me pictures of myself, like, 'So proud of you.' It's weird to have your aunts sending you naked pictures of yourself."

The Eternals, co-starring Angelina Jolie, Richard Madden, Salma Hayek, and Kit Harington, is set to hit theatres in November.