When is a draw a defeat? That's a conundrum for Juergen Klopp, who saw his Borussia Dortmund team draw 4-4 with Stuttgart in the Bundesliga match of the season on Friday.
The end-to-end thriller was significant not only for the staggering incompetence of the champions' defence but the fact that it allowed Bayern Munich to cut the lead at the top to just three points.
Another Dortmund win seemed inevitable when they led 2-0 late in the game. Then, 20 minutes of sheer folly:
71st min: Mats Hummels is left on his backside by a touch from beanpole defender Georg Niedermeier and Vedad Ibisevic strokes in. 2-1.
77th min: Hummels and Neven Subotic jump for the same header, allowing Julian Schieber to skip round a static Lukasz Piszczek, beat Hummels for a second time and poke in a remarkable solo effort. 2-2.
79th min: Schieber is too quick for the lunging dive of Subotic and scores from distance. 2-3.
81st min: Hummels shows why he was a centre forward in his youth by scoring from the edge of the box. 3-3. (Klopp says that at this stage the draw ''felt like a victory'').
87th min: Ivan Perisic slams in from a corner. 4-3. "I was depressed for five seconds, and then I started believing we could make it 4-4," said Stuttgart coach Bruno Labbadia.
90th min: Labbadia's belief is proved justified. Subotic misjudges a hopeful cross, confusing the hapless Marcel Schmelzer who plays the ball to Stuttgart's Christian Gentner. 4-4.
An unforgettable night for neutrals but Klopp ("that's football, that's life, that's totally mad") would have perhaps preferred a drab 0-0 to the enduring the sight of seven Dortmund players lying on their backs in disbelief as Gentner equalised.
As Arsenal found out last season, a 4-4 draw can have a destabilising effect on a title challenge and the question now is how Dortmund will respond at improving Wolfsburg on Saturday.
Suddenly, assumptions are being questioned, notably about Dortmund's defence.
Last season they conceded a stingy 22 goals in 34 games. Until April, the Fab Four of Piszczek, Schmelzer, Subotic and Hummels looked like breaking the record for the best defence in Bundesliga history.
Only twice did they concede more than one goal in a match - once on the first day of the season and once after the title had been wrapped up.
This season Dortmund conceded 17 goals in their first 27 games, last shipping twice at Hannover on 18 September. Then, Stuttgart.
If Bayern coach Jupp Heynckes is right when he says defences win titles, then prior to Friday Bayern should have given up the ghost. Suddenly that's all changed.
After Dortmund dropped two points, Bayern were crowing. Mario Gomez even sent a video message to his former teammates, featuring a group of Bayern players thanking Stuttgart for their comeback.
"It's in our hands now," pointed out Holger Badstuber after Bayern beat Nuremberg the next day to cut Dortmund's lead to three points.
The irony here is that Dortmund were the more impressive of the two title contenders at the weekend.
Bayern were awful in the Bavarian derby. Outfought by Nuremberg, they won the match thanks to a late piece of magic from Arjen Robben and a huge slice of luck when Manuel Neuer spilled a 35 meter shot from Almog Cohen onto his crossbar.
The message from Dortmund: don't panic.
"I've been more nervous than I am now,'' insisted former Bayern man Hummels. ''Our situation is - as it was before - optimal. We're leaders with a three-point cushion. There are worse positions to be in with six games to go in the season."
Though it felt like it, Dortmund didn't actually lose to Stuttgart and actually extended their record unbeaten run to 22 matches.
"Whoever says we're nervous is completely wrong. Now there's fighting talk coming out of Munich. We'll do well not to get caught up in that," Sebastian Kehl insisted.
Apart from having his worst game of the season, Hummels last week saw his father Herman dismissed as youth coordinator at Bayern (he'll be replaced by Franz Beckenbauer's son, Stefan).
Perhaps that's why he rose to the bait when Bayern president Uli Hoeness said the 11 April match between Dortmund and Munich will be the ''moment of truth.''
"The war-of-words is at a similar level to the battle for the title. It shows we have gained respect and how we are perceived by Bayern,'' Hummels said.
Just weeks ago the title seemed out of reach for Bayern. In the last ten seasons, only Stuttgart have come from seven points behind with ten games left to claim the title. Their amazing comeback at Dortmund might yet mean Bayern match that impressive achievement.