Ronnie O'Sullivan made it to the third round of the English Open with a 4-1 win over Ryan Day - but the match was not as straightforward as the scoreline might suggest.
Although the 44-year-old sped to a 2-0 lead, with breaks of 68 and 56, the Welshman halved the deficit with a century in the third frame.
And the fourth frame was finely poised, with O'Sullivan overcoming a break of 56 from Day to edge it 58-56.
In a scrappy fifth frame, though, with no sizeable breaks, O'Sullivan got over the line 68-37.
Day knocks in brilliant ton against O'Sullivan
Earlier, Judd Trump came back from 3-1 down against Yuan Sijun to win 4-3.
In the final three frames, the world number one secured breaks of 73, 83, and 67 to no reply from the Chinese player.
And Neil Robertson battled through with a 4-2 win over Englishman Mark Joyce in Milton Keynes.
'I probably played better than I felt I played...' - O'Sullivan after victory over Day
The Australian began proceedings with a century, but Joyce would win the safety battle in a tight second frame.
After successfully potting a long red in the third, Robertson got his breakthrough to move into a 2-1 lead.
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Into the fourth and the world number three left himself with a difficult green at 58-58, into the yellow pocket needing to hold for the brown, but he handled both excellently to extend his advantage.
Joyce responded with breaks of 72 and 54 to narrow the gap to just one frame, but it was Robertson who emerged victorious with a final-frame break of 76.
The 38-year-old will face either Mark Davis or Zhao Xintong, who play on Wednesday evening, in the third round.
Mark Selby beat Chang Bingyu 4-3, with a break of 125 in the deciding frame proving the difference.
Kyren Wilson is also through to the third round after a scrappy 4-1 victory against China’s Gao Yang, registering a high break of 82.
Ding Junhui progressed in the morning session after an impressive 4-1 win over Belgium's Luca Brecel. The Chinese player progressed thanks to breaks of 97 and 88 before rounding off the match with an excellent 137 clearance.
'Brilliant' - Robertson races to eighth century of season in style
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