World Championship 2017: Mark Selby beats Fergal O'Brien 10-2 in opener
Defending champion Mark Selby reached the second round of the World Championship by thrashing Fergal O'Brien 10-2 at the Crucible Theatre.
Leicester's Selby, who beat Ding Junhui in last year's final, looked on course for a whitewash by going 8-0 ahead.
Irishman O'Brien claimed the ninth and 11th to avoid becoming only the second player to exit without winning a frame, but Selby wrapped up the match.
He will face either Wales' Ryan Day or China's Xiao Guodong in the next round.
Selby has enjoyed a stellar season - claiming four ranking titles, including this month's China Open, though no player has followed that by winning the world title in the same season.
The world number one made top breaks of 92, 77 and 66 as he began his attempt to win his third title at the Sheffield venue, which is holding the event for a 40th year.
Having made light work of O'Brien, Selby has almost a week off, returning to action next Saturday.
Dubliner O'Brien came through qualifying by beating David Gilbert in a final-frame decider - the longest frame in snooker history, timed at two hours, three minutes and 41 seconds.
But he struggled badly in the first-round encounter, managing a high break of just 32, although he avoided the ignominy of joining Eddie Charlton - who lost 10-0 to John Parrott in 1992 - as the only players not to win a frame at the championship.
He has now lost six successive meetings against Selby, claiming just four frames in a run stretching back to 2006.
In an all-Scottish tie, qualifier Stephen Maguire claimed eight frames in a row to trounce Anthony McGill 10-2.
Maguire, who has won five ranking titles, has fallen to 24th in the world but was in good scoring form, compiling breaks of 97, 66 and 60 to go through.
Meanwhile, five-time champion Ronnie O'Sullivan was pegged back to a 5-4 lead over debutant Gary Wilson.
Former taxi driver Wilson fell 5-1 behind but took the last three frames of the session, including the ninth having needed snookers.
On the other table, Kyren Wilson leads 5-4 against Crucible first-timer David Grace.