Mixed Martial Arts expert Ronda Rousey, who stars in "Expendables 3", says Hollywood star Sylvester Stallone took her under his wings and helped her sail through the film's shoot.

"The Expendables 3" is gearing up for release in August, and recalling the time when she was cast by Stallone, she confessed that when she felt clueless about what she was doing and was confused, the veteran actor came to her rescue.

"Sly really took me under his wing. I know it was a gamble to bring me on to the film; he wrote the script, and there were bigger names thrown into the pot. But he believed in me from the beginning even though I felt like I was embarrassing myself on set," Rousey said in an interview to thehollywoodreporter.com.

"Sly told me, 'Don't ever be embarrassed. You're just playing. Some people take this stuff too seriously. We're really just playing pretend, and they pay you money for it'," she added.

The world premiere of 'The Expendables 3' will take place in London. It will release Aug 15.

It stars names such as Jason Statham, Jet Li, Dolph Lundgren, Randy Couture, Terry Crews, Arnold Schwarzenegger, Wesley Snipes, Antonio Banderas, Mel Gibson, Harrison Ford, Kellan Lutz, Kelsey Grammer, Victor Ortiz and Glen Powell.