Paris - Paris Saint-Germain travelled to Borussia Dortmund desperate to finally make their mark on the Champions League knockout stage but left on the receiving end of a defeat which threatens to derail yet another European campaign.

The aftermath saw an unhappy Neymar pointing the finger of blame at his own club with coach Thomas Tuchel clearly in the firing line.

The world's most expensive player scored a potentially precious away goal for the French club, but a brace by the exceptional Erling Braut Haaland gave Dortmund a 2-1 win to take to Paris for the return leg of their last-16 tie on March 11.

The danger is that a familiar story is unfurling for PSG, who had gone three and a half months unbeaten before their trip to Germany. Far too strong for their domestic rivals, but unable to cope with the step up in intensity at the business end of the Champions League.

Humiliated by second-leg comebacks at this stage by Manchester United last year and Barcelona in 2017, beaten by Real Madrid in 2018, it is four years since the Qatar-owned club won a Champions League knockout tie.

Sporting director Leonardo recently tried to remove some of the pressure going into the Dortmund tie when he said: "This is not life or death, it's a game of football."

However, another exit at this stage would be immensely damaging for the PSG project. Would Kylian Mbappe and Neymar, the two most expensive players in world football, really stick around for another crack at the competition?

Despite his goal, Neymar looked off the pace in Dortmund, short of match sharpness having missed his team's previous four games with a rib problem which he insisted was not serious.

PSG's desire to wrap the Brazilian in cotton wool for the last fortnight was understandable, after he missed the United tie 12 months ago with a foot injury and the second leg against Madrid in 2018 because of a similar problem.

But it proved detrimental, according to the player himself.

"The club decide, so sadly I had to respect their decision. But that ended up being bad for me and my teammates," he told Brazilian media after the game.

"I was genuinely injured, I had a fissure in a rib. But it was nothing that should have prevented me from playing.

"They postponed my return again, and then postponed it again and again.

"I understand the club's fear, because I missed the last 16 in each of the last two years. I respect the decisions, but it can't be that way, because it is the player who ends up suffering.

"It was very difficult to play a game of that intensity, for 90 minutes without stopping. If I were in a better condition physically then I definitely would have played better."

While Neymar appeared to point the finger at the club's medical staff as well as Tuchel, others were more directly critical of the coach.

After months of committing to a 4-4-2 formation which gave more room to fit in his many attacking stars but made them potentially more vulnerable at the back, Tuchel switched to a 3-4-3 in Dortmund, mirroring the opposition.

Sports daily L'Equipe called it "a tactical choice that had not been worked on and did not work out". Tuchel "lost his bet", the paper added.

"It is nothing to do with the tactical set-up, it is up to us to show the desire," insisted Presnel Kimpembe, a member of that back three.

Kimpembe's brother was rather less generous -- he launched a foul-mouthed tirade against Tuchel in a video posted on Instagram that went viral in France, although he did then claim it was "a joke".

Nobody of a PSG persuasion will be in the mood for laughing if they go out in the second leg, but the rest of Europe possibly will be, at their expense.