Ronnie O'Sullivan beat Graeme Dott 4-1 to progress to the semi-finals of the World Grand Prix in Llandudno , but called his performance 'diabolical ' . The 39-year-old did not reach the heights he is capable of , but was still more than good enough to get past the Scot - the man he beat to win the second of his five World Championships in 2008 . Ronnie O'Sullivan was in no mood to pat himself on the back after beating Graeme Dott . Neither man made a break of three figures and O'Sullivan missed a handful of easy-looking shots , but Dott was unable to punish him , most notably in the fourth when he missed a green off the spot as he tried to clear to level at 2-2 . O'Sullivan made him pay , but was in no mood to pat himself on the back . 'Graeme has had a good tournament , been consistent and is always a tough match , ' O'Sullivan told ITV4 . 'We both played poorly , I felt nervous for some reason and could n't see the wood for the trees . It was strange , one of those evenings and it was lucky Graeme played as badly as me . ' I was sitting there thinking of how good Stephen Hendry and Steve Davis were and they started twitching , and thought 'is this my time ? ' . I missed so many balls , it was diabolical . Martin Gould beat Peter Ebdon 4-2 to book a place in the last four in Llandudno . ' I 'm just relieved , tomorrow is another day , but you want to build momentum as this stage of a tournament . ' Earlier in the day , Martin Gould beat Peter Ebdon to ensure O'Sullivan would avoid a collision course with his old nemesis . He called the veteran , a man who has tormented him in the past , 'Peter f****** Ebdon ' in a newspaper interview this week , but Ebdon was dispatched 4-2 . O'Sullivan will face Stuart Bingham in the last four after he beat Mark Davis 4-0 in a low-scoring affair .
Ronnie O'Sullivan beat Stuart Bingham 4-1 to progress to the semi-finals . O'Sullivan will now face Graeme Dott in the last four in Llandudno .