Unterbuchner claimed the first set of the match despite being five points down in the averages and surviving a 170 checkout from the Dutchman.
A 15 dart leg at the right moment saw Mandigers making it all square in the early going.
Despite that, this clinical nature didn’t continue as it was Unterbuchner’s turn as he pounced on a missed set dart from Mandigers and from there he went on to claim victory meaning a good start for the German.
It was a good start also for Aileen de Graaf who edged past Kirsty Hutchinson despite going a set down; experience prevailed for one of the top seeds though as she moved through to the Quarter-Finals.
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Wayne Warren (92.75) 3-2 (91.11) Justin Thompson (R2)
Joe Chaney (86.27) 2-3 (86.22) Ben Hazel (R1)
Aileen de Graaf (72.99) 2-1 (70.15) Kirsty Hutchinson (R1 women)
Willem Mandigers (94.16) 1-3 (89.71) Michael Unterbuchner (R2)
Andreas Harrysson v John O’Shea (R1)
Deta Hedman v Laura Turner (R1 women)
Paul Hogan v Brian Raman (R1)
Martijn Kleermaker v Gino Vos (R2)