He uses the nickname "Marko9Gardinic" during video game competitions. Gardiner, from Hamilton, South Lanarkshire, plays football for amateur team Blue Dragon, in the Glasgow Chinese Football League. He scored 19 goals in the 06/07 season which netted him the prize of top scorer.
On 15 March 2008, Gardiner won the largest single prize in United Kingdom video gaming history. Playing Pro Evolution Soccer ( Party of European Socialists ), he won £50,000 inside Wembley Stadium, in the Play.com-sponsored Party of European Socialists Rankings tournament. He also finished second at the European Pro Evolution Soccer 6 Championships in Seville, Spain on 11 October 2007, and won the United Kingdom Championships held in London on 2 September 2007.
