As Muhammad Aman sat on the sidelines of the Matsumoto Yamaga Under-18 team's training at the Karigane Football Centre last week, he noticed a group of boys from the U-14 team limbering up before going for a run.
The U-14 team were supposed to train after the U-18s, but they were doing their own fitness training before the actual session.
"The Japanese players are very disciplined and that's why they are good at what they do," the 15-year-old Muhammad said.
The Pasir Ris Crest Secondary School student, who trains with the North East-ActiveSG Football Academy, was among six teenagers selected for a week-long trip to Matsumoto, Japan, where they trained with J2 League side Matsumoto Yamaga's U-18 team.
The trip was made possible by Epson, which is the shirt sponsor of both Yamaga and S-League club Geylang International.
Ho Jia Wei, 17, was the other ActiveSG Football Academy player chosen for the trip, while Afif Fikri and Muhammad Azri, both 15, were chosen from Geylang's Under-15 team. The remaining two, Gabriel Lee, 15, and Mohammad Riaz Jaleel, 16, were the most valuable players from the Epson Youth Challenge tournament in July this year.
In addition to training with the Yamaga youth players, the Singaporeans also stayed with them at the club's youth dormitory for most of the week.
"Every player is very professional when it comes to training, and they treat each session very seriously in order to get better," said Jia Wei, a Pioneer Junior College student.
They were also impressed by the Yamaga youths' first touch, accuracy in passing, positioning and speed of thought.
Despite the weather - the sun sets at around 4.30pm, with the temperature constantly under 10 deg C - Yamaga assistant U-18 coach Takahiro Nishino praised the visitors for their hard work.
The 37-year-old said: "This is a (foreign) environment for these kids but they did well, especially when they didn't understand what the coaches are saying.
"Technique wise, they are good, but they can improve more."
The boys promised to bring what they learnt back to Singapore, and apply those lessons to training.
Afif, a Meridian Secondary School student, said: "I hope to change my way of thinking (so I can) play more one-or two-touch football, and to work on my physical fitness as well."
Geylang Centre of Excellence coach and former Singapore international Samawira Basri believes the boys can match the Japanese if they put their hearts into it.
He said: "They have two legs, and so do we; it's just that they (the Japanese) want it more and push themselves to the max."