Zhou regains lead, needs two morepublished at 15:31 GMT
15:31 GMT
O’Sullivan 3-4 Zhou
Zhou’s break comes to a halt at the yellow, but O’Sullivan then leaves the same ball hanging over the top right pocket.
Zhou, who had been 64-0 behind then snatches the frame 65-64, the third time today he has won a frame on the black.
O’Sullivan, despite some superb, beautiful breaks, remains yet to be ahead in this match. He needs to win three of the next four frames or he is out at the first hurdle.