What Will Be Borussia Dortmund's Strongest Defence in the 2015/16 Season?

When Borussia Dortmund made the short trip along to Bochum on Friday night for their latest pre-season friendly, a quiet but confident mood hung over the travelling black and yellow army. Manager Thomas Tuchel's new side had looked good over the summer months, and many believed the 2. Bundesliga hosts would offer little resistance to the former German champions. 

Yet what followed was a full 90 minutes of end-to-end football that showed in part just what Tuchel's side could do in attack. What also came up was the manner in which Dortmund still looked susceptible to direct attacks on their own goal. 

Alas, Dortmund do look competent and somewhat vibrant in their attack, but when it comes to the back-line, there may still be a fair amount of work to be done between now and the start of the new season. 

Tuchel has a tough choice to make at left-back with regards to whether he'll stick with the tried-and-tested Marcel Schmelzer or go out on a limb and welcome young challenger Jeremy Dudziak in to his side. 

Schmelzer brings with him a wealth of experience and a handy left foot for crosses and set pieces, yet there's no denying that the German international can at times offer little but a weak spot for better sides to target.

As an attacking full-back, his natural game begins to show holes when he's asked to mark and hold a solid position across the back-line. The 27-year-old is essentially the most obvious option for the role but not necessarily the safest one. 

Of course, there's little that we've seen of Dudziak to suggest he can indeed come in and offer more than what Schmelzer already brings to the table. Like his more experienced colleague, the 19-year-old thrives with the ball at his feet and space to run into. 

Yet at this point it may be best to simply wipe the slate clean and start again. If Tuchel wants to make an impression on this side, he'll have to do so by fixing its faults. Despite all he offered Jurgen Klopp over the years, Schmelzer is indeed a fault in this team. For the coming season, Dudziak should be given a chance to prove himself. 

A similar struggle is indeed unfolding on the opposite wing where Erik Durm and Lukasz Piszczek will fight it out for the role of first-choice right-back under the new manager. Tuchel has looked to play both in equal measure over the course of the pre-season friendlies, yet there's no denying that one player is on the up and the other is very much on the down. 

Piszczek, who just turned 30, should be enjoying the best football of his career; for the past two seasons, however, he's looked far from the accomplished full-back that made him one of the most sought after in Europe. 

To add to that, Durm has continued to grow as a player after spending a large portion of last season and the year before on the left flank. He will now be hoping to tie down a regular gig on the right—a position he undoubtedly fancies as his own in the long-term. 

Shuji Kajiyama/Associated Press

The question for Tuchel is whether Durm's progress has already pushed him past a lowly Piszczek. In this instance the former, younger alternative may well prove to be more appealing to the new manager. Unfortunately in football, the old saying "out with the old, in with the new" is very much part of the modern sport. 

When we get to the matter of picking two central defenders, things become a little simpler because little has changed in the position in quite some time. 

There's no denying that when both are fit and not distracted by transfer rumours and stories, Mats Hummels and Neven Subotic are not only the best defensive partnership for Tuchel but possibly one of the best the club has ever seen. 

Tuchel will be fortunate that he has a truly impressive backup in Sokratis Papastathopoulos—who will feature heavily as the aforementioned two pick up knocks throughout the season—as he has rarely let the side down when called upon. Any team in Germany would be more than happy to start the Greek international week in, week out, but at Dortmund he will undoubtedly have to continue putting up with being third best. 

As such, Matthias Ginter—the club's fourth-choice central defender—will undoubtedly be an interesting one to watch this coming season. The young talent could of course find himself playing in midfield should Tuchel need cover, but there's little chance of him holding down a regular spot in defence while the other three defenders are fit and able. For now, he'll have to either put up with the reality of the situation or simply make moves to find regular football through a loan or a transfer. 

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