Williams plays for the University of Alabama's Crimson Tide football team, which on Monday night in the US will play in the national championship against Notre Dame University's Fighting Irish. The two teams are the nation's most powerful and their rivalry its most intense. The 80,000-seat stadium has been sold out for weeks and nosebleed seats were reselling for $US2600 ($2480) a month ago. Cable channel ESPN expects to break the record audience, set when 27 million watched last year's game.

In the middle of all this, playing the position known as nose tackle in the centre of Alabama's defensive line - the most feared defensive unit in the competition - will be 22-year-old Williams, an indigenous man born on Thursday Island and raised in Brisbane.

Williams stands 1.93 metres tall and weighs 145 kilos. In July this year he became a social media sensation when grainy footage of him bench-pressing 600 pounds (272 kilograms) spread across the net.

The Birmingham News's Crimson Tide roundsman, Don Kausler, says Williams has become such a formidable opponent because he combines speed and athletic ability with his size.

As a schoolboy in Brisbane, Williams played basketball and rugby league before friends suggested he try American football. He was discovered by Arizona Western high school and after a year there he was offered 40 college scholarships.

Williams learnt fast and was a terrifying presence on the field.

According to Mark Edwards, the editor of the Decatur Daily, Williams quickly secured a following among fans because he combined fearsome looks with a disarmingly friendly presence.

Williams wears his hair in a Mohawk and has covered his body in tattoos. "People like him so much it actually makes them want to go to Australia," says Edwards. "He is not at all affected, he is so laid back."

After the Tide won last year's championship, Williams travelled to Washington with the team to meet the US President, Barack Obama, at the White House.

This time Williams has already graduated, so when he comes off the field on Monday night he will no longer be an amateur. Most analysts predict Williams will be snapped up in the first or second round of the draft, and could pocket as much as $US4 million as a signing bonus. But first there is a championship to win.