Borussia Dortmund's summer signing, Nuri Sahin will be out for three weeks due to an inflamed tendon in his knee. 

The midfielder had to leave Dortmund's summer training ground in Munich, Bad Ragaz, so he could have some tests on his knee. After having the tests it was revealed that he would be out for up to three weeks. He played 45 minutes in Dortmund's 5-1 friendly win against Rot-Weiss Essen. 

This means he will miss the start of the Bundesliga campaign for the Die Schwarzgelben and also DFL-Supercup on the 13th August and their DFB-Pokal game against Stuttgart Kickers also. As well as Sahin being out, BVB are missing their German World Cup stars for these games

Add to that, this is the most crucial time of pre-season; Sahin will be cursing his luck. Dortmund, likewise, won't want another repeat of last season's injury fiasco, even though they have better squad depth than last term.