Rugby's big powers sized up their likely World Cup quarter-finals on Monday as the knock-out round began to take shape after the second weekend of action. Ireland's shock upset of in-form Australia looked to have blown the draw wide open with the odds now on northern and hemisphere teams being separated until the final on October 23. Teams refused to look too far ahead with about half the pool stage yet to be played. But Welsh assistant coach Shaun Edwards said Ireland had struck a blow for the northern sides. "I thought Ireland sensed an opportunity... and they showed that we can also play rugby a little bit in the northern hemisphere, not just in the southern hemisphere," he said. Rugby's heavyweights are understandably wary after a series of strong performances by the sport's lesser teams, including Canada's fighting loss to France on Sunday. Edwards hoped that Ireland's win, coupled with the new challenge posed by the minnow teams, would make for a more open and watchable World Cup. "Let's hope so because openness creates more and more interest," he said. "It's not much fun watching a competition where you know who's going to win it. "That's what will put people in front of their TV screens and get them turning up in their thousands (at games). I hope it's right because that creates more interest." The seven-week tournament takes a break on Monday before Italy play Russia on Tuesday, Tonga face Japan on Wednesday, South Africa take on Namibia on Thursday and Australia are against USA on Friday. After this weekend's action, the likeliest quarter-finals see Ireland against Wales, England against France, New Zealand against Argentina and Australia against defending champions South Africa. All Blacks assistant coach Wayne Smith said Ireland had set the blueprint for the tournament with their high-intensity, physical approach which muscled Australia out of the game. "The physicality of their game was way up compared to what we've experienced so we've got to get that really quickly," Smith said. "They've issued a blueprint for rugby in showing that nothing changes. If you win up front and you win the gain line and you win the collisions, then you're probably going to win the game. Meanwhile All Blacks winger Zac Guildford admitted he had a problem with alcohol and apologised for drinking "excessively" after last month's Tri-Nations defeat to Australia. A chastened Guildford told a press conference, organised to head off rumours about him, that he "had let myself down and let the team down... in making a few bad decisions off-field. "I'm taking positive steps to make sure it doesn't happen again," he said. The All Blacks denied Guildford's drinking was behind his non-appearance at the World Cup so far, while centres Richard Kahui and Sonny Bill Williams have both been used on the wings. A nightclub bouncer appeared in court charged with accessing a computer system for dishonest purposes after security footage of England centre Mike Tindall cosying up to a woman was posted on the Internet. And South Africa coach Peter De Villiers lived up to his reputation for outspokenness by maintaining that New Zealand's pre-match "haka" war dance had been seen too often during the World Cup, diluting its impact. "For me, about the World Cup especially, there is too many haka around," he told the Dominion Post newspaper. "It is unique, to me, and is losing its intensity, but that is only me. "People are becoming so used to it. It is not a novelty any more and they don't respect it." The comments sparked an angry reaction with All Blacks centre Ma'a Nonu leading the riposte. "It's one man's opinion. We do it because we want to and it's part of our history, our tradition, we're proud of it. I don't really care what he thinks," Nonu said.