Thompson averaged 91 in a straight sets win over Mal Cuming to move through to the first round.
He hit three 180’s and 50 percent (9/18) on his doubles on his way to the win and he will face Michael Unterbuchner in the first round.
Harms on the other hand came through in a dramatic last set decider against ‘Silverback’ who was making return to the Lakeside stage.
O’Shea despite losing the first set took the lead 2-1 including a brilliant 120 checkout to seal it.
Harms broke throw in the next set and then hit double eight to tie it up and send it to a decider.
He broke again on double nine in the next set to win the set 3-1 and then win the match 3-2 with a 87 average.
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Paul Hogan (88.08) 3-1 (78.27) Wesley Newton Sharon Prins (63.75) 2-0 (65.46) Roz Bulmer Mal Cuming (71.60) 0-3 (91.17) Justin Thompson Wesley Harms (87.90) 3-2 (84.90) Tony O'Shea