Brave Blossoms coach Eddie Jones said Wednesday that Japan's rugby resources were spread too thin and there needed to be a major shake-up in the way the game is run here.

Talking after Junior Japan (in essence Japan's under 20s) went down to their third straight heavy loss at the World Rugby Pacific Challenge, Jones said the 60-24 defeat to Tonga A was reflected on Japanese rugby.

"If players who are good at local level are not performing at international level, what does that tell you?" he said in an exclusive interview with Kyodo News.

"The Tongan team was a mixture of their local players and their under 20s and they train twice a week. The Japanese university players train six times a week. That tells you a lot about the preparation. The Japanese players are not prepared to play rugby. It's not the result of the coaching they are getting with the under 20s. The strength and conditioning programs at schools and universities are not good enough and the players have been exposed badly."

Jones said the decision to send the under 20s to a tournament in which the five other countries were playing their A XVs was made due to the small playing base in Japan.

"We need to maximize our resources. We can't have three national sides. That's why it's best to concentrate on the national side and the under 20s and see which of them (the players) are capable of playing at international level," he said, using Wales as an example.

"Three years ago their under 20s lost by 100 points to New Zealand. Now they are in the top four. That's because they concentrated on that side and had them training with the national team and on the national program."

In response to calls that some senior players should have made the trip to Fiji for the RPC, Jones said players who were good enough to play international rugby were better off training with the national side ahead of this year's Rugby World Cup.

"I don't think they can play international rugby," he said when certain players were mentioned, adding that a number of recent university "superstars" had been shown up when they played Top League rugby or trained with the Brave Blossoms.

"The mindset of many players here is simply to be successful in Japan. But there is a huge difference between being successful at domestic level and international level. We need to make players understand what is required to play at international level."

Jones said Fumiaki Tanaka proved what Japanese players could do with the right attitude and said he hoped one day the attitude of the Panasonic Wild Knights and Highlanders scrumhalf would be the norm for his compatriots rather than the exception.

"Super Rugby will hopefully enable the players to set a higher benchmark, but the problem is the whole structure.

"Look at New Zealand. How is it, a country of 5 million can be the No. 1 rugby-playing nation for so long? It's because they have the right structure whereby every tier is producing players and coaches who are good enough for the next level up. You go from club rugby to ITM Cup to Super Rugby and, if you are good enough to succeed, ultimately to test rugby."

Referring back to his theme that Japan's rugby resources and talent were spread too thin, Jones said that the size of the Top League meant there weren't enough high-quality games to prepare the players for international rugby.

"England is a Tier One nation and they have 12 teams in their Premiership. New Zealand has five (Super Rugby) sides and a Tier 3 level competition (ITM Cup) and South Africa has six and the Currie Cup is of Tier 3 level. Japan has 16 sides in the Top League. That's too many."

"Super Rugby will help the national team but is the Top League capable of producing Super Rugby players?" he asked, referring to Japan's entry into the Southern Hemisphere competition from 2016.

As for calls to go back to the way things were, Jones simply said.

"Do we want to go back to the way that has seen Japan not win a World Cup game in 24 years, saw them win just 40 percent of its tests and never make it into the Top 10. That's laughable."