National coach Kiatisak Senamuang admitted that Thailand still lag behind Asian giants after seeing his men outclassed by Japan in a World Cup qualifier on Tuesday night.
Goals from Genki Haraguchi after 18 minutes and Takuma Asano in the 75th minute gave the Blue Samurai a comfortable win at Rajamangala National Stadium.
In a one-sided match, the margin of victory could have been a lot more wider had Thailand goalkeeper Kawin Thamsatchanan not made a number of world-class saves.
It was Thailand's second defeat in as many games in Group B of Asia's final qualifying round for the 2018 World Cup.
In the other Group B games, Iraq were defeated 2-1 by Saudi Arabia and the United Arab Emirates suffered a 1-0 home loss to Australia.
After two matches, Australia and Saudi Arabia have six points each, and Japan and the UAE three each. Thailand and Iraq are still looking for their first point of the campaign.
In Group A are Iran, South Korea, Uzbekistan, Qatar, China and Syria.
The top two teams of each group automatically qualify for Russia 2018, while the two third-placed teams face each other with the winners taking on a Concacaf side for another berth.
"The players tried to do their best and tried to fix our weaknesses but Japan are very strong," Kiatisak said after Tuesday's match.
"We have to admit we did not play our best game. We were lucky that we did not concede much more goals. We have to improve a lot both in defence and attack.
"Every game for Thailand at this level is a hard game. There are no easy games for us. We have to admit the standards are different. But these are our the first steps and we will go forward from here. A 2-0 loss is not too harsh a result."
Thailand were without defensive midfielder Sarach Yooyen who was sent off in Thailand's loss to Saudi Arabia in the opening match and Kiatisak said his absence affected his team.
The Thais will next play two away games at the UAE on Oct 6 and against Iraq in Tehran on Oct 11.
"The match against the UAE will be another difficult game for Thailand,'' said Kiatisak.
Goalkeeper Kawin said: "We played according to the coach's plan but Japan were stronger. We have learned a lot from playing against them.
"We have to improve for our next matches. We must play better in the next games."
Led by midfielder Chanathip 'Messi Jay' Songkrasin and striker Teerasil Dangda, Thailand were outplayed by Japan who featured several Europe-based players including AC Milan's Keisuke Honda, Borussia Dortmund's Shinji Kagawa and Leicester City's Shiji Okazaki.
"That was a very important victory for us, but it was not easy. Our players eally showed great determination to win," said Japan coach Vahid Halilhodzic whose men lost 1-0 to the UAE in the first match.
"We created a lot of chances but maybe because of a lack of concentration we could not score more goals. But I can say in general that it was a good match on a difficult wet pitch. As usual we gave some presents to the opponents in one or two situations."
Goalscorer Haraguchi said: "I'm relieved. We lost the first game and just focused on three points. We have to get stronger and win the remaining eight games."