|Venue: The Crucible Theatre, Sheffield Dates: 15 April - 1 May|
|Coverage: Watch live on BBC TV, BBC Red Button, Connected TVs, online and app.|
Four-time Crucible champion John Higgins and world number four Ding Junhui were both made to battle before completing first-round wins at the World Championship.
Scotland's Higgins, 41, resisted a Martin Gould fightback to win 10-6.
World number 18 Gould trailed 7-2 overnight, but closed the gap to 8-5 before Higgins shook off the Londoner.
China's Ding also resumed 7-2 ahead and was pegged back to 7-4, but eventually saw off compatriot Zhou Yuelong 10-5.
Zhou, 19, took the first frame against his hero, however Ding continued his quest for a first world title with a steady recovery to back up his stunning performance in Monday's first session.
"I played well in the first session when he was a bit nervous. It was hard for him because he has no experience to play at the Crucible," said Ding, who now plays another fellow countryman, Liang Wenbo, in the second round.
World number 13 Liang beat Stuart Carrington 10-7 in a tense last-32 encounter that ebbed and flowed throughout.
Grimsby's Carrington was in sensational form early on, scoring three 100s and two 50s in winning five consecutive frames for a 5-2 lead.
Liang hit back, taking the final two frames of the morning session and edging ahead at 7-6, before closing out victory in an increasingly scrappy encounter.
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Five still alive
World number six Higgins, who plays Northern Ireland's Mark Allen in round two, made nine breaks of 50 or more in a high-quality match against qualifier Gould.
The 28-time ranking event winner responded as Gould began their second session with a century and was pleased with both his potting and margin of victory.
"To win 10-6 against Martin is brilliant," Higgins said. "He's a class player and at 7-2 up that brings pressure. Martin can roll off two or three frames very quickly.
"Had it gone 9-7 it would have been difficult to get over the line. I am very happy to get through."
McLeod fightback stuns Trump
World number 54 Rory McLeod won five frames in a row against second seed Judd Trump to overturn a 4-0 deficit and lead 5-4 after an incredible opening session.
Trump, the 2011 runner-up, looked certain to take a decisive overnight advantage against his fellow Englishman McLeod after scoring 50s in the first two frames.
But McLeod's unflappable approach seemed to disrupt Trump's rhythm after the mid-session break and he grew in confidence.
The 46-year-old - the oldest player left in the competition - began to show some fluency of his own as he closed out the afternoon session with a superb break of 77.
World number 10 Ali Carter also trailed 4-0 after the first session against Graeme Dott, but the two-time Crucible finalist was unable to turn things around and trailed the 2006 champion by the end of the evening.
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