Japan warmed up for the start of its 2018 World Cup qualifying campaign with a ruthless 4-0 win over Iraq in a friendly on Thursday night.

Keisuke Honda and Tomoaki Makino put Japan two goals ahead within the opening 10 minutes at Nissan Stadium, before Shinji Okazaki added another midway through the first half.

Substitute Genki Haraguchi then gave the 63,877 crowd one more goal to cheer as he made it four late in the second half, leaving manager Vahid Halilhodzic satisfied as he turned his thoughts toward Tuesday's opening World Cup qualifier at home to Singapore.