In the 43rd minute of Tuesday’s match between Bayern Munich and Borussia Dortmund, Joshua Kimmich took advantage of Roman Burki’s questionable positioning by delivering an extraordinary chip to put Bayern 1-0 up.
This would be the only goal of the match which saw Bayern extend their lead to seven points above Dortmund with six matches left to play. After the whistle, analytics site FiveThirtyEight published an updated predicted table for the Bundesliga giving Bayern a 98% chance to win the title.
So how have Borussia Dortmund, a side who spent £112.95m this season still fail to produce anything like a title challenge?
With an elite attack led by Marco Reus, Jadon Sancho, and Erling Haaland with support from other stars such as Julian Brandt, Thorgan Hazard, Achraf Hakimi, and Raphael Guerreiro, that arguably leaves the defending to blame. What do Dortmund need to do in the market to truly push for dethroning Bayern from their perch of Bundesliga dominance?
THE DEFENCE
Head Coach Lucien Favre has shown a strong preference for a back three this season, which usually sees three of Mats Hummels, Lukasz Piszczek, Manuel Akanji, and Dan-Axel Zagadou all played as central defenders. Mats Hummels is 31 but remains Dortmund’s most reliable defender without question. To his right is veteran fan-favourite Piszczek, who is now 34.
To Hummels’ left, a rotation of Zagadou and Akanji. Zagadou is only 20 and has shown he can start comfortably, but still makes the occasional mistake that young players make. Akanji is just 24 but has fallen out of favour this season due to a number of poor performances. This puts Dortmund in a situation of needing a true central defender to replace the converted Piszczek and the potential need to add another defender to compete with Zagadou, should Akanji be sent away on loan or sold due to his inconsistencies.
Also contributing to Dortmund’s defending is Hakimi, who will return to Real Madrid this summer from a loan spell that has seen him become one of the very best wing-backs in the world. Unfortunately for Dortmund, the young Moroccan will be unlikely to return due to the large transfer fee he would command, so they will need to look for his replacement.
That brings us to goalkeeper Roman Burki. The Swiss international has strong distribution, but his shot-stopping has proved to be a liability as he is, this season, the Bundesliga keeper* with the lowest save percentage (0.55) and fifth-lowest Post-Shot Expected Goals ratio, failing to save 4 fewer goals than he should have. At 29 years old, it is worth asking the question if he is likely to improve in the future.
METHODOLOGY
Dortmund are a club known for integrating youth players into the first team and turning them into elite players. In our data recruitment, we looked at all senior players in the world aged 26 or younger who have played at least 2000 minutes this season. This age profile fits Dortmund’s preferred method of recruitment which allows for a higher chance of selling for potential profit. Due to Dortmund’s spending last season and the current pandemic, the central defenders in the search have a maximum (Transfermarkt) value of £14m.
CENTRAL DEFENDERS
Favre looks for defenders who can win possession and then comfortably play the ball. After initially looking at 265 qualified players, a shortlist of seven players who are the closest fit to the style of play that Dortmund prefer looking for was made.
These players not only were comparable to Hummels in success rates but also in the quantity of attempts made for each category. In the table below, we have the seven players listed along with Hummels as a comparison player.
Defenders
| Player | Team | Duels % won | Aerial Duels % Won | Short-Medium Pass % |
| Mats Hummels | Dortmund | 71.69 | 62.58 | 95.07 |
| Strahinja Pavlovic | Partizan (Monaco) | 75.56 | 69.43 | 93.58 |
| Kristoffer Ajer | Celtc | 72.89 | 67.56 | 94.52 |
| Justin Hoogma | Utrecht | 68.57 | 61.68 | 92.86 |
| Marcos Senesi | Feyenoord | 70.16 | 56.82 | 93.24 |
| Ferro | Benfica | 67.89 | 62.82 | 92.81 |
| Lautaro Gianetti | Velez Sarsfield | 73.95 | 56.58 | 94.03 |
| Stefan Posch | Hoffenheim | 69 | 54.92 | 92.75 |
While these players look to be the best fit to reinforce Dortmund’s backline, two leading candidates emerge - Celtic’s Kristoffer Ajer and Monaco’s Strahinja Pavlovic. Ajer is a 22-year-old Norwegian capable of playing as a central defender as well as playing right-back and as a defensive midfielder. Standing at 1.97m/6’5” and valued at just £2.5m, he offers a commanding presence with a strong ability on the ball.
The Norwegian international has enough quality that he would be immediately able to slot into the starting lineup as a Piszczek replacement, but Dortmund will likely have to pay a fee much larger than his value due to reported interest from Real Madrid, Manchester City, and Leicester City.
An option Dortmund could explore as either an alternative to Ajer or as competition for Zagadou is Pavlovic, who is currently on loan at Partizan from Monaco. The Serbian youth international is another commanding player, standing at 1.94m/6’4” and is already valued at £6.48m.
Being left-footed, he would be a prime fit for Dortmund on the left side, but he may need a bit of time before he can be fully trusted as a starter due to a lack of high-quality first-team minutes. Pavlovic would likely drive a transfer fee of around £10m, so the thought of bringing in a player at that cost would likely be largely dependent on what Dortmund decide to do with Akanji.
WINGBACK
Two players emerge as the best two candidates in this shortlist; Alan Mozo and Tomasz Kedziora. Mozo creates an interesting option for a number of reasons. First off, he is an excellent progressive passer and a strong crosser (the best of the shortlist, in fact.)
However, he is the worst on the shortlist for defensive duel win %. The 23-year-old Mexican made the 2018 Liga MX Official Best XI and is starting to see opportunities for the national team, so a move to a bigger league could see him become a more regular player for Mexico. For Dortmund, he is a player valued at an affordable £1.8m and could likely be purchased for £5m, making him a low risk.
Defenders
| Player | Team | Prog Pass % | Right Cross % | Defensive Duel win % |
| Achraf Hakimi | Dortmund | 74.5 | 32.3 | 62.9 |
| Tomasz Kedziora | Dynamo Kyiv | 79.89 | 43.09 | 63.96 |
| Mergim Vojvoda | Standard Liege | 78.39 | 30.91 | 61.43 |
| Michael Murillo | Anderlecht | 71.02 | 38.89 | 65.9 |
| Vyacheslav Karavaev | Zenit | 79.47 | 31.43 | 65.5 |
| Alan Mozo | Pumas | 79.47 | 31.43 | 65.5 |
| Aurelio Buta | Antwerp | 75.19 | 35.4 | 60.14 |
| Nordi Mukiele | RB Leipzig | 75 | 31.94 | 75.88 |
| Deyovaisio Zeefuik | Groningen | 71.49 | 30.86 | 70.78 |
A different option to Mozo is Dynamo Kyiv’s Kedziora. Kedziora is 25, so he is likely not going to be the replacement to reach Hakimi’s heights, but he could be a valuable short-term option while Dortmund may look to the academy or finding a new wonder kid who is available for cheap. The Polish international may be keen to work with compatriot Lukasz Piszczek and offers similar abilities to what Mozo brings. With a value of £2.52m, Dortmund could realistically even consider bringing in both Kedziora and Mozo to battle for the starting spot for less than £10m.
If Dortmund wish to bring in a high profile name, Nordi Mukiele is the best option. However, the RB Leipzig star would likely command a fee of £40m if not more. Leipzig have no reason to sell to Dortmund, and realistically, Mukiele has no true need to join Dortmund right now given Leipzig’s current status within the Bundesliga. BVB could likely only afford Mukiele if they were to sell Jadon Sancho and not look to bring in a different right winger for the role that would likely be filled by Thorgan Hazard or Gio Reyna.
GOALKEEPER
While Roman Burki is a respectable Bundesliga goalkeeper, he is not the goalkeeper that will win you the title. Instead, he is more of the player who helps you solidify a spot for the Europa League or helps push for a Champions League spot. He will make some great saves but will also make some blunders. Unfortunately for Dortmund, they need a goalkeeper that can help push them to the next level.
The top candidate to replace Burki is Dominik Livakovic of Dinamo Zagreb, who is valued at £9.45m and is battling Lovre Kalinic as Croatia’s first-choice goalkeeper. The 25-year-old is an outstanding shot-stopper and a strong distributor, which is highlighted by saving 7.28 goals above what he is expected. Dinamo Zagreb are a club known for selling talent to larger leagues, with the most recent being Dani Olmo to RB Leipzig for £17.1m. Livakovic would likely draw a fee between £15-20m, which would be on the upper end of a comfortable fee for Dortmund.
A Bundesliga option who could be an alternative to Livakovic is Paderborn’s Leopold Zingerle. Zingerle is currently sitting at the bottom of the Bundesliga and, at age 26, may not sound like the most attractive option. However, Zingerle has saved 0.4 more goals than expected, while Burki has saved 4 less than expected, and faces the second most shots on target per game in the league. Zingerle is not as strong of a ball-playing goalkeeper as Burki, but in terms of shot-stopping, he is an upgrade to Burki while facing the same demands, making him a potential steal that could cost less than £5m.
CONCLUSION
Borussia Dortmund have a very talented attack, perhaps one of the best in the world, but a defending unit that needs a lot of work if they wish to win a Bundesliga title in the near future. These players are all options who could help increase Dortmund’s chances, but video analysis will need to be done to reinforce the data standouts.
Dortmund will need to replace Achraf Hakimi this summer as not only is he not affordable at £54m (Transfermarkt) but also probably not for sale at all. With that being said, he will be a crucial asset to replace as he has become not only a key defender for Dortmund but also a key member of their attacking play. Replacing Hakimi will require finding a replacement who is strong in progressive passing, accurate in crossing from the right side, and of course capable of winning defensive duels.
If you liked this article and are interested in more like it along with data visualizations, you can follow Aidan on twitter @ARDataAnalysis.
*= Bundesliga goalkeepers with a minimum of 1,000 minutes played in the league for 2019/20
Kristoffer Ajer 
Łukasz Piszczek 
Dan-Axel Zagadou 
Manuel Akanji 
Bayern 
