Shane Geraghty and Tim Payne have inadvertently given every Guinness Premiership club an incentive to play on Sundays during the Six Nations.

Leicester chief executive Peter Wheeler fears clubs could look at exploiting an anomaly, highlighted by England internationals Geraghty and Payne, which has been created by the new player release deal between the clubs and the Rugby Football Union.

The £110million eight-year agreement allows England team manager Martin Johnson to decide during the autumn internationals and Six Nations which players within his 34-strong elite player squad he will send back to their clubs.

In case there are injuries, Johnson keeps two players outside the match-22 for away games, with London Irish back Geraghty and London Wasps prop Payne retained as back-up for last Saturday's clash with Wales in Cardiff.

However, both were unused and while Geraghty missed Irish's 14-9 home defeat by Harlequins that day, Payne played in Wasps's 36-29 home win over Leicester 24 hours later.

With Wheeler's side getting the rough side of the deal, he will raise the issue during a review of it involving the clubs and RFU with any recommendations going to the Professional Game Board.

Wheeler said: "The fact Payne played against us will have been noted by other clubs and you don't want to create a stupid situation where everyone opts to play on Sunday in the hope that their squad men will be released.

"We cannot afford to have any situations which affect the credibility of the Guinness Premiership and anomalies that have arisen will be examined by the review.

"Patently, this is the first year and Martin Johnson has the leeway to release players during the Six Nations period when he feels it is beneficial. However, while he has sent George Chuter back to us at Leicester this weekend, he cannot make any club pick a particular player."

Bob Casey, the London Irish captain, has been released this weekend by Ireland having missed the Quins defeat because he played for the Irish A team. Geraghty is also available for Irish when they travel to Bath on Saturday, along with fellow EPS men Steffon Armitage and Paul Hodgson.

Casey said: "I knew Shane had to stay with England last Saturday and it's a bonus to have him with us this weekend but I didn't realise Tim had been able to play for Wasps."

Gloucester director of rugby Dean Ryan has been a critic of the agreement and said: "It's clear that any club that doesn't play on a Sunday is penalised in a situation like the one involving Shane and Tim. I can't see how you can really determine it is working because of the problem areas that are emerging."

RFU officials insist the rules are clear and that Johnson has established good lines of communication with the directors of rugby at the clubs. However, it is already apparent the review body has a number of anomalies to sort out.

There has been some good news for the RFU, though, as Gordon Brown has revived England's faltering bid to host the 2015 Rugby World Cup, despite a staggering £80m guarantee demanded by International Rugby Board chiefs.

The Prime Minister gave his backing following a meeting with RFU management board chairman Martyn Thomas and sports minister Andy Burnham.

Brown said: "Rugby is one of the great sports and I believe we can win the Rugby World Cup bid in 2015."