Ashton eased past Rhian Griffiths of Wales in straight sets 2-0 at the Lakeside Country Club, in English village Frimley Green.

It set up a quarter-final tie for the 2014, 2015 and 2017 winner with either Australian fifth seed Corrine Hammond or England's Fallon Sherrock.

Adams, meanwhile, fell at the first hurdle while chasing a first global crown since his third title in 2011.

The former England captain took second seed Mark McGeeney to a sudden-death leg and crucially hit the bulls-eye to throw first.

But McGeeney cruised into the lead and had six darts to win it before eventually sealing victory with a double top. 

Dutch 10th seed Willem Mandigers won 3-0 against Wales' Nick Kenny elsewhere.

England's Scott Mitchell, the 2015 winner, defeated Darius Labanauskas of Lithuania 3-2 while women's top seed Deta Hedman of England began her pursuit towards a first world title by defeating Rachna David of Norway, 2-0.

Gary Robson of England also secured a first round clash with top seed and defending champion Glen Durrant when winning a preliminary round match, 3-0, against Pengiran Mohamed of Brunei.