Bayern Munich\'s Dutch midfielder Arjen Robben is injured and will miss his club\'s first fixture of the upcoming season on August 1. Robben had to be replaced in the 63rd minute of Bayern\'s friendly game against AC Milan on Tuesday after suffering a knock to his thigh. \"I hope it\'s nothing serious,\" said Bayern coach Jupp Heynckes. The injury has ruled him out of Monday\'s first round cup tie. Bayern will also be without Frack Ribery for the game against Eintracht Brunswick after the France international suffered a left ankle problem in training. Ribery may also be absent for Bayern\'s first league fixture against Borussia Monchengladbach on August 7.