The Lithuanian hit six maximum scores to beat the Dutchman, who had seven perfect darts in the nineth leg. Labanauskas faces Joe Cullen in the second round on Saturday.
Brendan Dolan overcame James Wilson to reach the last 32 and will play compatriot Daryl Gurney tomorrow. Michael Barnard won the first tie of the tournament as he defeated Krzysztof Ratajski 6-4.
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Schedule of Play
Friday June 8
First Round
Afternoon Session (1pm local time, 12pm BST)
Krzysztof Ratajski (87.99) 3-6 (95.83) Michael Barnard
Jeffrey de Graaf (95.71) 4-6 (95.94) Darius Labanauskas
Brendan Dolan (88.22) 6-4 (88.97) James Wilson
Matt Padgett v Mike De Decker
Andy Boulton v Ritchie Edhouse
Hannes Schnier v Roy Asquez
Toni Alcinas v Steve West
Jamie Lewis v Ross Smith