Mack Horton: Get to know Australia's first Rio gold medallist.

Mackenzie ‘Mack’ Horton has scored Australia’s first gold medal win of the Rio Olympics, storming home to win the 400m freestyle on the Games’ opening day.

The 20-year-old from Malvern, Victoria touched just ahead of China’s defending champion Sun Yang to propel himself into Australia’s Olympic history books.

So who exactly is Australia’s latest champion? Here’s five facts about Horton.

1. Poor eyesight no hindrance

Horton is easily recognised by many due to his large frames that he pops on as soon as he’s on dry land.

The short-sighted swimmer needs thick prescription goggles to compete.

Horton’s eyesight is so bad that without his glasses or goggles he could “barely see my hand in front of my face”.

2. A swimmer scared of the water?

Horton began swimming at 10 to, believe it or not, help him overcome his fear of the water.

Just three years later he broke his first Australian record at 13 years old.

Although Horton says he does not remember a specific moment he decided to pursue swimming seriously, his father says it was when he met Grant Hackett at age 11.

3. An impressive record

Although he narrowly missed out on selection for the London 2012 Olympics, finishing second in the 1,500 metres freestyle trial, he has made impressive strides since.

In 2013 at the World Junior Championships in Dubai he took an incredible five gold medals and five championship records.

He went on to win silver at the Glasgow 2014 Commonwealth games, and bronze in the 800 metres freestyle at the 2015 World Championships in Kazan, Russia.

4. Head in the game even while sleeping

‘Mack the Knife’, as he is sometimes known, used to sleep with a piece of paper above his bed with a list of age record holders for the 1,500 metre freestyle.

5. Future business man?

Horton is not putting all his eggs in the swimming basket, and in between training studies commerce online at the Australian Catholic University.

He once said “I want to find the equivalent of the 1500m in the business world.”

This post originally appeared on ABC News.

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