Fergal O'Brien's two centuries were too much for Higgins

O'Brien trailed 4-3 to Higgins before hitting breaks of 142 and 114 in the last two frames to secure victory.

Ronnie O'Sullivan fought back from 4-2 down to beat Tom Ford 5-4.

"I was hoping to get a chance and in the end I fell over the line and I'm pleased to win. It's in my blood not to come second," said O'Sullivan.

I'm thinking of buying a house there as I'll be going there O'Sullivan on China

The Rocket, who lost to Marco Fu in the final of the Royal London Watches Grand Prix last month, has just returned from a promotional trip to China.

The two-times world champion said he would consider buying a property in the country.

"I haven't had any time to practise since Aberdeen, I spent a bit of time with my family then went to China," he said.

"But I don¿t need to practise as much as some other players. I've had a demanding schedule but I'm fit and able to recover.

606: DEBATE Who do you think will come out on top in Belfast? Saj C

"I had a great time in China, I love it and they look after me. I'm thinking of buying a house there as I'll be going there more often. The future of snooker is good there."

Meanwhile, Stephen Hendry needed a break of 127 in the eighth frame to fight off a comeback by Martin Gould and win 5-3.

Double Crucible champion Mark Williams suffered a 5-3 defeat at the hands of home favourite Gerard Greene.

O'Brien's 142 was the tournament's highest break so far.

"He played better than me," said Higgins.

"I was garbage. I missed so many easy balls. I ran out of position a lot. He just played better than me. It's just one of those things."

Higgins took a 4-3 lead with breaks of 68, 44 and 44 but then could only watch as O'Brien swept into the last 16.

"It doesn't get any better than knocking in two tons to beat the world number one and world champion," said O'Brien, who won the 1999 British Open.

I was garbage. I missed so many easy balls. He just played better than me. John Higgins

"I've made a good start to the season, it's a been a good year so far," he added.

Hendry let a 4-1 lead slip to 4-3 before his century ended Gould's resistance.

Williams and Greene, who reached the semi-finals of last month's Aberdeen Grand Prix, both complained that their table was playing badly and took an early interval at 1-1.