The Stuttgart striker missed Friday\'s clash with Vietnam due to a sore knee which has been troubling him for some time, but he believes he\'ll be right for Tuesday\'s qualifierShinji Okazaki says he believes in good enough condition to play in Japan\'s 2014 World Cup qualifier against Tajikistan on Tuesday despite missing Friday\'s friendly win over Vietnam due to a knee problem.The 25-year-old VfB Stuttgart striker remains in some doubt for Tuesday\'s qualifier due to the sore right knee which he said had worsened following the long trip to Japan from Germany.However, Okazaki told reporters at Japan training over the weekend he believes he will be right to play.\"I think I will be okay to play. I\'ve been playing with discomfort in the knee for a while and it just felt a bit worse when I got here,\" he said.\"I don\'t think it\'s just practice but travel and everything else that has made it hurt a bit more but I think I am in good enough condition to play now.\"Okazaki was rested by Japan coach Alberto Zaccheroni for the 1-0 friendly win over Vietnam where the Samurai Blue struggled to adjust to a 3-4-3 formation against a defensive opponent.The former Shimizu S-Pulse man commended his team-mates for grinding out the win against the Vietnamese who put plenty of players behind the ball.\"This kind of game happens against Asian opposition. They come at us as challengers but we basically shut them out and got the result,\" Okazaki said.He continued: \"We got bunched up in the middle of the park a bit too much and maybe could have got forward a bit more.\"It\'s okay to look at ourselves and see where it went wrong but I don\'t think we were that bad.\"