Mark Selby and Stephen Maguire race into second round, Ronnie O'Sullivan struggles against Wilson

The world No 1, and defending champion, raced to an 8-1 lead in the morning and, despite a battling performance from the Irishman in the evening session, when he took the second frame and had a shot to take the third, Selby slotted a long black to clinch a straightforward win.

Stephen Maguire also triumphed by the same scoreline against Anthony McGill. He won for the first time at the Crucible for five years, taking eight frames on the trot after the scores had been tied at 2-2 in the morning session.

He will face either Judd Trump or Rory McLeod in the second round, while Selby will take on Ryan Day or Ziano Guodong.

75-20, 91-2, 82-14, 70-33, 77-0, 79-41, 83-0, 95-5, 19-66, 92-4, 57-73, 54-50

Centuries: None

12-116, 64-6, 47-61, 81-28, 0-97, 0-72, 0-88, 0-78, 0-79, 1-60, 0-73, 52-77.

Centuries: None

Ronnie O'Sullivan struggled to make his class tell in the first round against Gary Wilson.

The Rocket raced into a 3-1 lead, picking up his first century of the tournament in the fourth frame, before Wilson fought back to 5-3 at The Crucible.

O'Sullivan then narrowly missed a red to the middle pocket, which ended up costing him a three-frame lead as Wilson won an epic safety battle to clinch the final exchange 69-78 with a tough last black to the corner.

The match will be completed from 2.30pm on Sunday.

74-41, 64-0, 125-0, 0-91, 122-0 (122), 65-58 (respotted black), 44-70, 0-99, 69-78

62-51, 90-18, 56-70, 76-0, 0-75, 49-41, 71-24, 0-70, 26-74 (to finish at 10am on Sunday).

Centuries: None