Japan Under 23s coach Makoto Teguramori has included JEF United striker Ado Onaiwu in a 21-man roster for an international friendly against South Africa on June 29.<br /><br />Ado Onaiwu, who has Nigerian heritage, was among the four attackers that made the squad list.<br /><br />Born in Saitama 20 years ago to a Nigerian father and a Japanese mom, the attacker has been given a final opportunity to impress Teguramori, with the manager set to name his 18-man squad for the Games on July 1.<br /><br />Onaiwu will be keen to represent Japan at the Olympics, with Japan set to face his father&rsquo;s country in their opener before meeting with Colombia and Sweden.<br /><br />He was in the Japanese squad for the 2016 Toulon Tournament in France.<br /><br />Igho Kingsley <br /><br /><br />