Sonny Bill Williams takes on Quade Cooper in Iron Man trailer remake

Code-hopping sports star Sonny Bill Williams has been cast ahead of Robert Downey Jr in an alternative version of the Iron Man series - and an Australian rugby icon has landed the role of villain.

In a crafty trailer produced by YouTube channel BsporTV, shots of Williams playing rugby and appearing at press conferences have been mixed in with various sequences from the Iron Man films.

The result is a truly dramatic storyline that pits the much-loved All Black against the man Kiwi rugby fans love to hate - Wallabies first-five Quade Cooper.

"Today is the first day of what's left of your life," the theatrical narration states, as a clip of Williams staring at Cooper angrily ahead of the 2016 Wellington Sevens tournament pops up.

Other shots of Cooper getting crunched in a tackle by Richard Kahui at the 2011 World Cup - and the Kiwi-born Wallaby kneeing Richie McCaw in the face - are also used to stoke the supposed rivalry between the two players.

In reality, Williams and Cooper are good friends off the field, and have shared snaps of themselves training together on social media.

Watch the full-length trailer below.