 Mason lost in the first round of the 2002 PDC World Championship to Dave Askew, but reached the quarter finals in 2003 – losing to eventual champion, John Part.He missed most tournaments in 2003 and 2004 while he served a prison sentence – but he returned to play in the 2004 World Grand Prix in October, and reached the quarter-finals of the event for the third time, this time losing to Steve Beaton.Mason has many titles to his name including the Irish Masters and the Vauxhall Pro Open on 3 occasions.