Jason Momoa has signed on for 'Guardians of the Galaxy'.

The 'Conan' actor gave such a convincing screen test as Drax the Destroyer for Marvel's upcoming adaptation of the superhero comic book series that producers decided to offer him the part immediately, according to Latino Review.

Jason reportedly beat off stiff competition from Isiah Mustafa, Dave Bautista and Brian Patrick during the audition last Wednesday (13.02.13).

The 33-year-old star will play key Guardians member Drax, a human whose family was slaughtered by villain Thanos, the evil being introduced at the end of 2012's 'Avengers Assemble'. He was given a chance at revenge by the Titans, who put his spirit into a powerful new body in order to oppose and eventually destroy Thanos.

Jason will join 'Zero Dark Thirty' actor Chris Pratt in the sci-fi flick. Chris was recently cast as lead character Peter Quill, also known as Star-Lord, an astronaut who returns from space as a galactic warrior.

The vocal casting for lead female Gamora, as well as for Rocket Raccoon and Groot have not yet been announced, but Adam Sandler and Jim Carrey are reportedly in talks to pick up the latter roles.

'Guardians of the Galaxy' is scheduled for release in August 2014.