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.