Ronnie O’Sullivan makes strong start to the Northern Ireland Open against Lukas Kleckers

O'Sullivan, who won the Hong Kong Masters seven days ago, put together breaks of 66, 71 and 52 at Belfast's Waterfront Hall to book a showdown with fellow Englishman David Grace.

Defending champion and home favourite Mark Allen also made it safely through, the Northern Irishman beating Chang Bingyu 4-1.

Allen lost a scrappy opening frame but then made breaks of 123, 56, 70 and 108 as he restricted Chang to just one point in the last four frames.

Three-time winner Judd Trump also eased his way into the second round courtesy of a 4-1 victory over Rod Lawler, while Kyren Wilson beat Ken Doherty 4-0 and former world champion Mark Williams made a break of 128 as he recovered from 2-1 down to beat Peter Lines 4-2.

Neil Robertson and Shaun Murphy enjoyed 4-0 wins over Fraser Patrick and Xu Si respectively, while Mark Selby was made to work far harder before overcoming Reanne Evans 4-2.