Japan celebrate their win over Samoa (Gallo Images)
London - Rugby World Cup organisers declared the pool phase of the tournament to be a "breathtaking shop window for the sport" on Monday and said the key to its success was the increased competitiveness of the Tier Two nations.
Record ticket sales, packed fanzones and massive TV audiences have enabled World Rugby to hit or surpass most of their tournament targets off the pitch, while officials have been delighted with the action on it during the 40 pool games.
"This has been a breathtaking pool phase," World Rugby's chief executive Brett Gosper told reporters at Twickenham.
"As our shop window for the sport we couldn't be happier. It is already the biggest Rugby World Cup and we are confident that on so many levels it will be the best."
The 2.41 million tickets sold, with an average of 97 percent capacity, surpasses the previous best 2.3 million for France 2007 while 750,000 people have watched games in fanzones.
More than 11 million U.K. TV viewers tuned in for England's games against Australia and Wales, while a surprising three million watched in Germany.
The most remarkable figures were in Japan, however. Around 800,000 people watched their opening match against South Africa but after Japan won it in the biggest-ever World Cup shock, the audience rocketed to 20 million for their next game against Scotland and hit 25 million for the Samoa clash.
"It really is showcasing the game to record audiences and engaging and inspiring new audiences around the world," said Gosper.
Organisers said the key to the attractiveness of the opening phase has been the more competitive performances by countries previously brushed aside.
Japan, who had previously secured one victory in seven tournaments, won three games this time round while Georgia, Tonga and Romania had moments to remember.
Namibia and Uruguay, the lowest-ranked teams in the tournament who have suffered monumental thrashings in the past, have also been much more competitive, with the key change coming in the final quarter of games when the outsiders' improved fitness means they no longer collapse.
The average winning margin in all pool matches is down to 24 points from 28 in 2011 while the margin in matches between Tier One countries (those in the Six Nations and Rugby Championship) and Tier Two is down to 30 from 36.
"That reflects why we are committed to investing in structures and technical help in the Tier Two countries," said Gosper.
While somewhat frustrated that hosts England are no longer involved, Gosper said the World Cup would not suffer.
"The tournament is a juggernaut and it goes on," he said.
"It's been an extraordinary few weeks and we hope it will continue in that way."