Mark Allen tonight embarks on what could be the biggest weekend of his life.

It’s a weekend that could climax on Sunday evening with Allen crowned Pokerstars.com Masters champion, the game’s most prestigious accolade outside that of World champion.

In tonight’s quarter-final at Wembley Arena, Allen faces Mark Selby who beat the Antrim cueman at the same stage last year.

“I am out for revenge against Selby and feel my game is in good order,” said Allen.

The winner will meet either Stephen Maguire or Ryan Day in tomorrow night’s semi-final with the final on Sunday.

Ronnie O'Sullivan was again thoroughly underwhelmed with his performance after beating Peter Ebdon 6-3 in their quarter-final yesterday.

O'Sullivan delivered a scathing appraisal of his game after fighting back from 3-0 down to beat Neil Robertson in the last round, saying a lot of the time he was playing “sub-standard shots”.

There appeared little to be unhappy with early on yesterday as the Essex potter raced into a 4-0 lead in just over an hour, but he was especially unhappy with how he finished the contest.

“Peter could have won the game quite easily,” he said.

“I would rather be 3-0 down and hit a bit of momentum than be 3-0 up and feel like I'm stalling when I come to the table.

“Most of the time I'm missing a lot of shots and it was difficult to find confidence out there.

“The long game I've got at the moment is just laughable.”

O'Sullivan got off to a flying start as breaks of 92, 53 and 74 in the opening three frames helped him seize control of the match.

Ebdon stopped the rot by taking the fifth frame and the 2002 world champion reduced the deficit to two by edging a tight sixth.

O'Sullivan eventually secured victory and in tomorrow afternoon’s semi-final will take on Mark Williams, who beat Shaun Murphy 6-4 last night.