Borussia Dortmund open their Bundesliga campaign against Hamburger SV at the Signal Iduna Park tonight carrying real uncertainty into the new season. The tone was set last weekend when Bayern Munich won the Super Cup 2-1 at Dortmund's own ground, a result that exposed defensive fragility and left Niko Kovac's side with more questions than answers before a competitive ball had been kicked in the league.

The injury situation at the back is a serious concern. Nico Schlotterbeck, the defensive leader, suffered a ligament injury at the World Cup and remains weeks away from returning, with his comeback now unlikely before October. Emre Can is also out, and Ramy Bensebaini was taken to hospital after the Super Cup with a suspected rib injury. Dortmund go into tonight's match without three natural centre-back options.

Off the pitch, the squad dynamic has been tested publicly. Fabio Silva made clear after the Super Cup that he wants more starts, while Kovac responded firmly that Serhou Guirassy remains the number one striker. Silva is reportedly attracting interest from clubs in Spain, and the situation could still change before the transfer deadline on September 1. Dortmund also missed out on Barcelona's Hector Fort, who chose Real Sociedad after negotiations broke down over the fee.

There are positives. New signing Konstantinos Karetsas impressed on his debut in the Super Cup, and the Champions League draw handed Dortmund a manageable group with Inter Milan, Arsenal and Aston Villa among their opponents. Sport director Lars Ricken has set the last 16 as the minimum target. The Bundesliga season starts now, and Dortmund need a result to build momentum.