[1] He then produced a series of major upsets at the 2008 World Championships (despite having a lower three-dart average than 3 of his 5 opponents, and failing to achieve a three-dart average of over 90 at any stage of the competition), beating Terry Jenkins in the first round, then Mick McGowan and Barrie Bates and three-times former finalist Peter Manley to reach the semi-finals.
He then defeated Wayne Mardle, who had been installed as tournament favourite after his upset victory over Phil Taylor in the previous round, 6–4 in the semi-final and met John Part in the final on New Year's Day, when he scored the lowest average by a finalist in the PDC World Championship during his 2–7 loss.
Shepherd is still the only darts player in PDC history to not score a three-dart average of above 90 in any round of a single World Championship and reach the final.
[citation needed] However, Shepherd was unable to continue his form throughout 2008, losing out in the last 64 in the UK Open and failing to qualify for the Las Vegas Desert Classic and the 2008 World Matchplay championship.
Shepherd entered the 2009 World Championship as the number 23 seed and faced Jan van der Rassel in the first round, losing 3–2 in a tie-break.
This was followed up in November 2009 by winning 2 of his 3 group games in the 2009 Grand Slam of Darts to reach the second round, where he lost 5–10 to Kevin Painter.
On 14 February 2021, Shepherd managed to regain his tour card beating Jack Main 6–1 in the final of the first day of 2021 PDC UK Qualifying School.