London (AFP) - Defending world snooker champion Mark Selby eased into this year's quarter-finals after a 13-6 victory over China's Xiao Guodong in Sheffield.
The 33-year-old Englishman rattled off the three frames he needed right at the start of the session.
"I played a really solid game. I didn't make too many mistakes and put him under pressure. And when he made mistakes I capitalised," Selby told the BBC.
Selby, who has recorded just one century break so far in the tournament, said he felt confident he had something in reserve.
"I feel like my game has not been fantastic," he told the BBSnookler c. "But it's not been poor. I am happy with that going into the quarter-finals.
"My opponent will know that when they play against me they will be in for a battle. I never give in and that has always been my philosophy."
In the quarter-final Selby will play Hong Kong's world number eight Marco Fu, who edged past 2010 champion Neil Robertson of Australia 13-11 in an nervy battle to reach his fourth quarter-final.
Fu lost the first two frames of the final session to trail 10-8, but a 115 break levelled at 10-10.
As the pressure mounted Robertson took a scrappy 21st frame on the black before Fu regained his composure to secure the next three and victory.
"It was very tough. I had so many chances and missed so many chances," the 39-year-old Fu told the BBC.
"It was one of those matches that neither of us deserved to win. For fighting spirit I was a 10 out of 10, but for snooker it was four out of 10."
A disappointed Robertson labelled his display as "garbage".
"I played awful snooker," said the Australian. "It wasn't good to watch. I was awful in my first match too."
Selby and Fu were joined in the last eight by England's 2013 finalist Barry Hawkins, who closed out his second round match 13-6 with Scotland's 2006 champion Graeme Dott.
Hawkins, who turned 38 on Sunday, like Selby wasted little time in bringing his game to a close, winning the three frames he required.
"You want to finish off as quick as you can because it's a long tournament," said Hawkins, who will play Dott's compatriot Stephen Maguire in the last eight.
"Over the years I have had some unbelievably gruelling matches and it takes it out of you."