Ivory Coast's African Player of the Year Yaya Toure is doubtful for their opening World Cup group game with Japan on Saturday, coach Sabri Lamouchi told the Ivorian press on Tuesday. The 31-year-old Manchester City star -- whose performances and 20 goals for his club last season were instrumental in bringing them the Premier League title -- is still struggling with a hamstring injury he suffered in the title deciding win over West Ham on the last day of the league season. Toure, who could be in line to be named African Player of the Year for a fourth time based on his performances for Manchester City, is pivotal to Ivory Coast's hopes of reaching the knockout stages for the first time. They failed to progress from the group stage in 20006 and 2010 but Lamouchi's side have been given a kinder draw this time round with aside from Japan their other opponents being Colombia, who are missing their talismanic striker Radamel Falcao, and goalshy Greece.