The win puts them level on points at the top of the group with Beijing Guoan and as the two sides have an identical head-to-head record, a place in the quarter-finals could be decided on goal difference.

The Japanese side could therefore be thankful for this mauling, which follows a 9-1 rout of the Thai side in the opening game in March.

Midfielder Danilo and striker Takuya Nozawa both scored twice, adding to goals from Daiki Iwamasa, Shizo Koroki, Yuzo Tashiro and the creative Mitsuo Ogasawara.

Iwamasa notched the opener when he rose highest in the box to nod in from a corner in the 19th minute and just two minutes later, Koroki powerfully headed home Ogasawara's free-kick.

At the other end, Krung midfielder Phichitphong Choeichiu struck a free-kick inches wide but it was to be a rare chance for the Thais and normal service resumed with Tashiro heading in on the stroke of half-time.

Kashima added a fourth immediately after the restart when Nozawa collected Toru Araiba's cross from the left and fired home from close range, and Ogasawara made it five when he surged into the box with a mazy dribble and slotted in.

Nozawa grabbed his second just after the hour mark when he headed in another accurate Ogasawara set-piece, shortly before a Danilo double completed the rout with two headers.

Krung had the last say, however, with Peeraphong Pichitchotirat scoring a consolation.