Premiership relaxes ground rules for clubs to avoid another London Welsh style legal battle over promotion The PGB judged that increasing the number of clubs to five would allow enough "headroom" to accommodate sides without it to gain promotion from the Championship. It is also understood that the PGB consulted Tim Ward, one of the QCs who sat on the independent panel, to ensure the new rules would be legally robust. The Championship clubs, however, have warned the RFU and Premiership Rugby that the revised minimum standards could still be open to a legal change, but that was dismissed last night by a PGB spokesman. "We are confident that the revisions to the MSC meet the requirements of all parties," he said. Premiership Rugby remains adamant that other minimum standards criteria, such as stadiums with the minimum capacity of 10,000 and medical requirements, are crucial to underpin future growth of the league. Meanwhile, Castres flanker Ibrahim Diarra will appear before a European Rugby Cup disciplinary hearing in Dublin on Wednesday after being cited for stamping in Sunday's 10-8 Heineken Cup victory over Glasgow. A report commissioned by the New Zealand government into the impact of the 2011 Rugby World Cup has revealed it boosted the country's economy by NZ$1.73billion (£896million) between 2006 and 2012. The tournament organiser, Rugby New Zealand 2011, posted a loss of NZ$31.3million but the event attracted more than 133,000 international visitors to the country - twice the initial estimated figure - who spent an estimated NZ$390million.