If the ball is difficult to handle in these conditions - and it seems to be - Wales will do well to use that powerful maul of theirs as much as they can.
Even during these lean times for Wales, their rolling maul has often been a weapon.
Unfortunate for Dan Edwards, whose clearance from his own half goes beyond the dead-ball line and Japan have a scrum midway through the Wales half.
Faulua Makisi dips into a tackle from the Scarlets man and the Japan back-row's head makes contact with Macleod's chest.
TMO Glenn Newman advises referee Luke Pearce to award a penalty, play is brought back to the Welsh half and Japan fly-half Seungsin Lee kicks his team's first points.
This time the lineout is good and here is a prime attacking position for Wales.
Japan's defence is good and, after a series of phases that don't go anywhere, Wales scrum-half Kieran Hardy has the ball ripped off him and the home side are able to clear.
Time for the first drinks break.
It's boiling hot in Wales too. Calippos for breakfast?