Aguirre has his work cut out in rebuilding Japan
(Neymar 18, 48, 77, 81)
For the longest time, Japan have been one of the strongest footballing nations in Asia and always one of the favourites for the Asian Cup.
From their abject performances at the World Cup Finals in Brazil to the rebuilding process after that, the Blue Samurai have lost their aura of invincibility.
Granted, there was no shame losing to one of the world's strongest teams in Brazil in a glamour international friendly at the National Stadium last night.
And, Japan's Mexican coach Javier Aguirre is still searching for his perfect line-up - he rested the likes of Keisuke Honda, Yuto Nagatomo and Mike Havenaar and opted for youth yesterday.
But the manner in which they lost 4-0 to the five-time world champions at the National Stadium has raised more questions about the fallen giants' fighting spirit, a topic that has been raised in Aguirre's previous three matches in charge.
Perhaps they were missing the creativity of the injured Shinji Kagawa, or the benched Honda, but the Blue Samurai simply couldn't find their way in the final third in the first half.
Brazil custodian Jefferson practically had nothing to do other than to take goal-kicks for at least the first 30 minutes of the match.
And that is considering that the four defenders ahead of the Botafogo goalkeeper - Danilo, Miranda, Filipe Luis and Carlos Gilberto (David Luiz was injured and didn't play at all) - are hardly considered world-class defenders.
Yu Kobayashi connected sweetly with a Kosuke Ota cross in the 24th minute, but sent his volley sailing over the crossbar.
Shinji Okazaki came closest to scoring in the 55th minute, when the Mainz forward hit the post from an acute angle after being picked out with a perfectly weighted through-ball.
Even the introduction of Honda at the start of the second half for Ryota Morioka did little to spark the Blue Samurai into action.
Perhaps Aguirre was experimenting and Japan were not in full flow, but neither were Brazil.
Japan have already lost their No. 1 status in Asia - the 48th-ranked team are now second to Iran (44th) on the continent.
And they stand to lose even more, namely their Asian Cup title in Australia next January, if Aguirre does not get his formula right, and soon.