Duff will face either Robert Thornton or Scott Mitchell in the battle of the two favourites for the title after dispatching of Keith Deller with ease 3-0 in sets.
Deller said that he would bring a better game than his opener against Mike Huntley but it was the WDF World Champion who advances paying heed to that.
After a slow start to the game, Duff hit back-to-back 180's before holding and then took the opening set on double three with Deller well back.
Setting up the 161 instead of going for it, Duff then claimed the second set with a 58 checkout.
Deller thought Duff couldn't hit the 144 to begin set three and he was proven right with advantage going to Mr 138 but sent to a decider, Duff hit the fifth 180 of the match at the right time before taking it with a break of throw.
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He was joined by another player in Dudbridge who could be a serious contender for the title. 'Flash' also on debut dispatched of Glen Durrant yesterday and it was another player of recent memory as opposed to yesteryear that fell to the former World Master.
It was a 3-1 success for Dudbridge in sets who will now have Kevin Painter in his sights tomorrow.
Jenkins seemed to take control in the opening set thanks to a 68 checkout but it was Dudbridge who pinned double five after Jenkins missed two for the set to lead. It was a Flash finish in the second set as he hit a 118 checkout but Jenkins came back with Dudbridge missing darts for 2-0 in sets and it was 1-1.
But Dudbridge hit double 16 to continue a superb tie and make it 2-1 and after six perfect darts to start the next set. He wrapped up the tie on double four last dart in hand.