Last season, Juergen Klopp emerged as one of European football's best coaches. Despite having led Dortmund to improbable back-to-back Bundesliga titles, he was largely under the radar until his BVB side took on heavyweights like Real Madrid and Manchester City in the Champions League.
And after getting the better of Jose Mourinho's Real and finishing top in the group stage, Klopp again outfoxed the Portuguese tactician in the semifinals as he affirmed his place among Europe's best coaches.
Although Dortmund lost in the Champions League final, Klopp can even take some credit for Bayern Munich's win. After seeing Bayern lose all three of their head-to-head matches with BVB in 2011-12, including a 5-2 drubbing in the DFB-Pokal final, Jupp Heynckes adapted his tactical style to incorporate Klopp's famous high-intensity gegenpressing.
The result? An unprecedented treble.
Klopp's tactics may have changed over the years, but his character and attitude toward coaching have remained consistent since his early years at Mainz. Above all else, Klopp emphasizes the importance of passion, emotion and attitude.
When his Mainz were promoted to the first division, he took the team for a five-day preseason camping trip at a lake in Sweden. The players were allowed to bring no food and did not even run for fitness training, let alone play with a football. But the experience built toughness and camaraderie.
"We went to the Bundesliga and people could not believe how strong we were," said Klopp, per Donald McRae of The Guardian.
Klopp is a mentor to his players, the kind of "cool dad" character who is half friend, half father figure. His passion inspires players to give everything for the club and to never, ever give up hope. He emphasizes that every game is important and that every goal is special: Rather than showing his team video footage of Barcelona's tiki-taka style of play, he instead uses still photos to illustrate how the Catalan giants celebrate every goal as though it were their first. That, to him, is a much more important lesson than subjecting his side to a brand of football they would not use.
On the pitch, Klopp has always used a daring, high-energy game plan. The value of his cavalier system was perhaps evident from his very first season at Dortmund, when he led a relegation-battling side to a sixth-placed finish in the Bundesliga. But it was only two seasons later, after Klopp had built a team capable of winning the Bundesliga, that gegenpressing gained widespread acclaim.
Fundamentally, gegenpressing is a rather simple tactical approach: A team simply plays at full pace for 90 minutes, approaching every moment as though they are down a goal late in a major final. After losing possession, players will swarm their opponents, giving them no time on the ball regardless of position and location.
According to Klopp, gegenpressing is the best playmaker there is. And he has good reason: Pressing has led to many goals for BVB, a perfect example of which being Robert Lewandowski's opener against Real Madrid at the Signal-Iduna Park last October.
Without the ball, there is not much that distinguishes Klopp's gegenpressing from the system Pep Guardiola used at Barcelona, especially in his first season. But what distinguishes Klopp is how his team plays once they've won back the ball. BVB's system is to always look for the opportunity to counterattack, playing the ball forward immediately and sprinting into open space as opponents shift from attack to defense.
In its most pure manifestation, which was best executed in 2010-11, gegenpressing utterly overwhelmed Bundesliga opponents. But it took some adjustment for BVB to become the power in the Champions League that they were in 2012-13.
In the 2010-11 Europa League and the 2011-12 Champions League, Dortmund were eliminated in the group stage. They were found naive and inexperienced, but a certain degree of their shortcomings could be attributed to their playing at an unsustainable and absolutely breakneck pace.
As criticized as Barcelona have been for lacking a "Plan B," their tiki-taka style is more versatile than the original manifestation of gegenpressing: It serves the purpose of creating attacking play, and when Barca are ahead, it can be used as a defensive measure to keep the ball away from opponents. Klopp's system was purely one-dimensional, and the risk of all-out attack was that BVB wore little time off the clock when in possession. On an off day for their finishing, Dortmund were vulnerable.
Even when BVB did manage to finish, they were sometimes found lacking. After going 2-0 ahead of Marseille at home in their 2011-12 Champions League group stage finale, they managed to lose 3-2. In that match, Dortmund's outfielders covered an incredible 122.9 kilometers. For perspective, that's 12.3 kilometers per player (including even the center-backs), or 43 percent more than the 8.6 kilometers Lionel Messi covered in Barcelona's Champions League opener against Ajax last week, recorded by UEFA.
Dortmund were unable to cope with the added burden of Champions League games while playing at such a high intensity, and their pace didn't even help. They entered the midseason break behind Bayern in the league table and already knocked out of the Champions League. Something needed to change.
Klopp has since adapted his team's style to include more finesse. Dortmund now cover less ground and, in domestic play, try to take a commanding lead early before taking a foot off the pedal and using more of a containment method. For example, when BVB beat Hamburg 6-2 earlier in September, their outfielders collectively covered a modest and manageable 112.0 kilometers, according to the official Bundesliga website. With the game decided long before full time, there was no need to go all out, and Dortmund's stars conserved their energy.
Even with their new-found willingness to tone down their attack, Klopp's game plan is somewhat one-dimensional.
Dortmund struggle to defend in a classical sense, deep in their own half. And for all their abundant ball-playing class in midfield, they aren't the best at simply maintaining possession and passing the ball around the middle third or playing a containment style of football—it is perhaps this above all which tactically made the difference between Bayern's treble-winning 2012-13 and BVB finishing without a trophy last season.
Klopp's system at Dortmund is not perfect; even with recent adjustments, it remains rather one-dimensional. But at 46, he is a very young coach who has done incredibly well in his limited years. He is the creator of a new tactical movement that has been emulated by some of Europe's strongest clubs, and those tactics have transformed BVB from a relegation-battling side to one of the world's elite clubs.