Ding Junhui of China plays during the Welsh Open snooker tournament in Cardiff, UK, February 12, 2020. /VCG
China's top snooker player Ding Junhui and five-time world champion Ronnie O'Sullivan were tied at 8-8 after Saturday's second session at the Snooker World Championship.
The pair shared the first eight frames on Friday before they took four frames each in the second session on Saturday, starting with 4-4.
Then Ding claimed the next three with breaks of 64, 118 and 101 to race into a 7-5 lead.
English player O'Sullivan went on runs of 90, 89 and 73 to regain the lead in just over half-an-hour, despite the fact that he has not reached the semifinals at the tournament since losing to compatriot Mark Selby in the 2014 final.
But Ding came back in the final frame of the session, by sinking this black to set a 49-0 advantage and eventually went on to make 53 to level things up again at 8-8.
Ronnie O'Sullivan of England takes a rest during the Snooker World Grand Prix in Cheltenham, UK, February 6, 2020. /VCG
They will resume the battle in the final session on Sunday with the first to win 13 frames to go through to the quarterfinals to face three-time world champion Mark Williams of Wales.
Barry Hawkins and Neil Robertson were also tied at 8-8 while Anthony McGill trailed Jamie Clark at 8-7. Kyren Wilson led Martin Gould 11-5.
(With input from Xinhua)
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