Cerezo Osaka forward Yoshito Okubo struck two first-half goals as Japan beat Bahrain 5-2 in the preliminary round of the soccer competition at the Asian Games on Tuesday.
After a disappointing opening display against Palestine, the Under-21 side found some form in the first half and went 4-0 up inside 41 minutes but a lack of concentration shortly after the break let Bahrain back into the match.
Masakuni Yamamoto made just one change from the side that started in Saturday's 2-0 win, bringing in Naohiro Ishikawa on the right wing after the FC Tokyo midfielder impressed after coming on for the second half.
Japan opened brightly at a deserted Ulsan Stadium with captain Takeshi Aoki going close from a header in the 12th minute, although Mohamed Ahmed Salmeen was unlucky with a header at the other end a minute later.
After 17 minutes, Japan got the breakthrough. Daisuke Matsui knocked a deep Ishikawa back across the goal to Okubo who made no mistake with his header from close range.
Three minutes later, Satoshi Nakayama made it two with a perfectly placed header from the edge of the area and after setting up the first two goals, Matsui scored himself, finishing off an Okubo center from the right in the 27th minute.
Bahrain pulled themselves back into the game at the start of the second half with two goals in three minutes.
After Shohei Ikeda was harshly judged to have pulled down Mohamed Jaffar Aizain, Rashid Rahman Saif sent Takaya Kurokawa the wrong way from the spot and with Japan still regrouping, Bahrain grabbed a second through Salman Isa Ali.