Gaping holes exist in the labyrinthine round-robin system that has been employed for the early stages of the Royal London Watches Grand Prix in Aberdeen this week, including scenarios that can lead to unusual betting patterns.

When Stephen Maguire, the 2004 United Kingdom champion, played Barry Hawkins in their closing match in group G on Wednesday, his job was already done. Having been successful in his first four matches, Maguire was certain to top the group and qualify for the last-16 knockout stage.

While Maguire was lacking motivation, Hawkins, the world No 19, had an obvious incentive. He needed to beat Maguire and hope that Stephen Hendry lost to Paul Davies. Both results came to pass, Hawkins winning 4-1 and Hendry losing 4-3 to Davies, the world No 62.

It emerged yesterday that a large number of bets, some substantial, had been placed with Betfair on Hawkins to win. Even though Hawkins would normally have begun as the outsider, cash was still being staked when his price became 1-10.

There was an angry reaction from many of the exchange’s snooker traders, but Clive Everton, who commentated on every shot of the match for the BBC, believes that those alleging match-fixing should take the circumstances into account. “This is an inbuilt problem with the system,” Everton said. “Maguire looked flat and uninspired from the outset, but that could have been down to having nothing to play for. He had already qualified and there was only a handful of people watching in the arena.”

The ATP Tour experimented with a series of round-robin tennis tournaments this year, but it invited heavy criticism and the idea was swiftly jettisoned. This is the second time that groups have been incorporated into the Grand Prix and Steve Davis, the former world champion, maintains that it should be the last. “I don’t like the format,” Davis said, a day before Hawkins and Maguire met. “It is open to abuse and you could be placed in a position where you have to rely on other people’s performances, which no player likes. You have matches where players don’t have their hearts in it.” The World Professional Billiards and Snooker Association, the sports’s governing body, refused to comment.

Neither Maguire nor Hawkins went any farther in the event. Maguire was beaten 5-3 in the last 16 by Liu Song, of China, while Hawkins lost 5-2 to Peter Ebdon.

Ronnie O’Sullivan, who eased through his group unbeaten, compiling five century breaks, reached the quarter-finals by beating Michael Judge 5-2. O’Sullivan, who now plays Joe Swail, has become the favourite to collect the £75,000 first prize after a surprise 5-4 win for Marco Fu, of Hong Kong, over John Higgins, the world champion, last night.

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