Borussia Dortmund suffered the first defeat of the season at the hands of newly-promoted Union Berlin causing them to lose plenty of ground in the Bundesliga in the blink of an eye. It's too early to make such claims, but this is not a game they would have expected to lose, and the points lost may be three points too many in the larger scheme of things.
Dortmund went a goal behind – not for the first time this season – when Marius Bulter scored in the 22nd minute. But all seemed normal when Paco Alcacer equalized only three minutes later. A second goal from Bulter early in the second half would've been enough on the night to get the home side a win, but Sebastian Andersson scored their third in the 75th minute.
Let's also take a moment to recognise the gravity of this win for Union Berlin whose first-ever Bundesliga win comes as a massive scalp, beating Dortmund at home. The home team who have impressed since the start of the season will be buoyed by this performance and the points. Having said that, let us look at the talking points from the game.
#3 Union Berlin pulled off a Borussia Dortmund
Anyone who saw Dortmund take on Bayern Munich in the German Supercup a few weeks ago would've recognised a key feature of the team Lucien Favre puts on the pitch. His sides are compact and organised, very capable of hitting teams on the break and full of energy, particularly at the end of games when the opponent's energy resources are dwindling.
As Union Berlin hosted Dortmund, Favre was haunted by a ghost of last season where his side were rendered ineffective by organised opposition who refused to cede space in their final third. Favre's solution was to commit more men in attack.
Berlin dealt Dortmund a lesson from their own playbook, remaining compact at the back and breaking quickly on turnovers to make Dortmund pay the ultimate price.
#2 Incoming players in a changed starting lineup failed to impress for Dortmund
Axel Witsel and Thorgan Hazard, who had started both games prior to this fixture were ruled out with injuries ahead of this tie. Julian Brandt and Thomas Delaney had stepped in and on paper, they are able replacements. Achraf Hakimi was also brought in, displacing Nico Schulz.
Before the start of the game, they seemed straightforward swaps and perhaps justified as well, given Hakimi and Brandt's contributions off the bench in previous games. That form, however, failed to translate to the pitch.
Brandt and Hakimi were both very involved in the game but while the Turkish international was guilty of being too predictable with the ball, Brandt was perhaps too inaccurate. On a number of occasions, the German international had opportunities to play in teammates but his pass was often wayward.
Delaney did a fair job in midfield but was taken off after he suffered a blow to the head. Dahoud, who came on to replace him, showed more initiative going forward, but couldn't link up with the likes of Reus and Sancho ahead of him.
#3 A few worrying habits for Dortmund
For the third time in as many games this season, Borussia Dortmund found themselves conceding the first goal of the game. In the other two cases, Dortmund stepped up a gear and were able to sweep aside the opposition. But it increasingly seems like they need the opposition to score for them to take the initiative in the game. It is not a healthy habit for title challengers, as Berlin showed on the day that Favre's side may not be able to do it in every game.
Furthermore, the goals that Dortmund have conceded have largely come from two sources - counter-attacks and corners. Favre is determined to win the games against weaker opposition this season that his side may have failed to win last season, which often leaves this side open to quick counters.
They were also found wanting when it came to the organisation of the defence on set pieces, conceding two of their goals against Berlin from well-worked corners.