Welsh Open: Mark Selby, Ronnie O'Sullivan and Ding Junhui suffer shock defeats
World number one Mark Selby and Ronnie O'Sullivan have been knocked out of the Welsh Open.
Iran's Hossein Vafaei defied a world ranking 37 places below Selby to win 4-3 in the last 16 in Cardiff.
Joe O'Connor, ranked 102nd, beat world number eight Ding Junhui 4-1 to reach the quarter-finals.
Earlier, Switzerland's Alexander Ursenbacher, ranked 71 in the world, beat five-time world champion O'Sullivan 4-2.
However, Ursenbacher's celebrations were short-lived as he fell 4-2 against China's Zhao Xintong in the last 16.
Stuart Bingham will face Zhao in the last eight while Joe O'Connor will play Scotland's John Higgins.
Neil Robertson will take on Kurt Maflin while Scott Donaldson faces Vafaei.
Higgins beat England's Jack Lisowski 4-3 to make the quarters, having earlier beaten another Englishman, Craig Steadman, 4-2 in the third round.
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