So are Bayern Munich in danger of not winning the Bundesliga for the the first time in five years? "It was a top performance from us".
But with two of those coming in front of the Bayern faithful at the Allianz Arena, where you would expect Ancelotti's men to be dominant and ruthless in front of goal, fans could be forgiven for being perhaps a tad fearful going into tomorrow's match at Signal Iduna Park.
BVB have qualified for the last 16 of the Champions League with two games to spare, they are still in the German Cup, and victory against Bayern this weekend would take them to within three points of the champions.
Marco Reus' long-awaited comeback for Borussia Dortmund has been delayed and he will not return against Bayern Munich on Saturday.
Reus was expected to be back in the Dortmund squad after six months out for the big Bundesliga clash after finally recovering from his adductor injury. RB Leipzig also have 24 points equal as the league leaders. Bayern have had a near flawless start to the Bundesliga season and despite of that head coach Carlo Ancelotti is taking nothing for granted ahead of Der Klassiker and took time out before the match to praise his opposite number, while also suggesting they may have a few weaknesses in defence. Hardly a crisis, but Guardiola set dizzyingly high standards.
Douglas Costa and Renato Sanches were both sent on to form an extremely attack-minded Bayern side and they had the Westfalenstadion holding its breath in stoppage time when Lewandowski headed inches wide from close range. For a team that usually hoards clean sheets like stolen doubloons, this is a jarring state of affairs.
An acrobatic Thiago Alcantara effort was about as close as Bayern came to testing Roman Burki, until a rebound off Franck Ribery nearly sneaked inside the Swiss goalkeeper's left-hand post.
Leicester surprised everyone last season by running away with the Premier League title, and Tuchel feels the Bundesliga newcomers are capable of a similar shock in Germany.
Bayern aren't playing that badly, but with a club of their stature and recent record, every fault is scrutinised.
But it wasn't just Bayern boss Carlo Ancelotti that was left disappointed after the game, but also former Bayern Munich midfielder Lothar Matthaus with defender Mats Hummels' actions off the pitch, rather than on it. This is their first ever season in the German top flight, and if they finished above the team that has ruled the Bundesliga, it would be one of the greatest triumphs in football history.
A goal early in the first half from Pierre-Emerick Aubameyang sealed the win for Thomas Tuchel's side and brought an end to Bayern's unbeaten start to their league title defence.