However, rather than dwell on his misfortune, the 30-year-old midfielder used the experience in Germany to drive him on to greater heights, so much so that he now looks set to be an integral part of Japan's challenge in South Africa this summer.

In the intervening four years, Endo has become the heartbeat of a Gamba Osaka side that won the 2008 Asian Champions League, the Emperor's Cup twice, one J.League Cup and finished third in the J.League three times.

He has also established himself in the national team under Takeshi Okada and while some players may harbour lasting bitterness over the events of four years ago, Endo felt disappointment only at Japan's failure to progress to the knockout stage.

"My only regret from the 2006 tournament was that our team and I myself couldn't get through the group stage," Endo told Press Association Sport.

"It is hard to get into a first team as it has only 11 places and I suppose I was not good enough to win the full trust of then-coach Zico at that time.

"Because I couldn't play there in 2006, however, I have worked harder on developing my game. So, it turned out to be good for me, I suppose."

Four years ago in Germany, Japan succumbed to an Australia fightback as they went down 3-1 in their opening match, conceding three goals in the last nine minutes.

The team from the Land of the Rising Sun then drew 0-0 with Croatia before bowing out to Brazil 4-1 in the third game of the group stage.

"That tournament made me realise the significance of the first match (in a tournament) again, as well as the importance of preparation, both in fitness and mentality," recalled Endo, who has more than 90 caps for Japan and made his senior debut in November 2002.

"The World Cup finals draws great attention from all over the world and are different from other games.

"However, it is no good for you to do anything special in your matches just because of that. It is important to have self-control and play in a relaxed manner.

"My ideal playing style is one like Barcelona but the bigger the tournament is, the harder it is to perform with your ideal playing style. Whether you score a lucky goal or an ugly goal, a goal is a goal, and that decides the winner.

"We should be strong enough not to fall apart in any situation. If we can improve our communication between the players and train well, we should be all right."

Endo's J.League journey began in 1997 when he joined Yokohama Flugels after finishing high school in Kagoshima.

When the Yokohama club disbanded at the end of the 1998 season, he moved to Kyoto Sanga in 1999 before joining Gamba two years later.

Endo was also a member of a Japan Under-20 team that finished runners-up at the 1999 World Youth Championship in Nigeria but his development at Gamba has been largely down to the arrival of manager Akira Nishino in 2002, as he was allowed the freedom to take charge of a game on the pitch.

"I would often tell my thoughts to coach Nishino and that has increased year by year," said Endo.

"It is the players who play on the pitch and feel what is going on in the game.

"At Gamba, we the players make amendments to our positioning or move according to the situations, without waiting for instructions from our manager.

"This can be a rarity at other clubs but it is thanks to the high calibre of coach Nishino."

Endo also revealed that even at 30 years of age, he is still trying to improve and learn from his fellow professionals, citing former Japan international and Flugels midfielder Motohiro Yamaguchi and Carlos Tevez of Manchester City - whom he played against in the 2008 Club World Cup when the Argentinian was at city rivals United - as examples.

"I always try to take good things from the players around me, even from players in a different position," he said.

"I watched how Moto-san (Yamaguchi) played and tried to pick up something from his game, such as how to play under pressure.

"Tevez also impressed me in the Club World Cup. He is not physically big but plays without committing errors and is good at using his body. 'How can I be like him?' I kept thinking that during the game."

With the World Cup just around the corner, Endo is hoping he can now make four years of hard work pay off on the world stage when Japan take on Cameroon, Holland and Denmark in South Africa.

"We couldn't do well in the previous tournament, so I would like to play this time and experience the responsibility of playing for the country as one of 11 players," he concluded.

"I want to do well for our team to get good results by putting to good use what I have now learned. I would like to make it a good World Cup."