Peter Stöger's side suffered their first defeat of 2018 after another unimaginative display against RB Salzburg. They will have to turn it around next week without the support of their boycotting ultras.
Borussia Dortmund face an uphill battle to reach the quarterfinal of the Europa League after a 2-1 home defeat to Red Bull Salzburg in Thursday's last-16 first leg.
A quick-fire brace from Valon Berisha gave the visitors a 2-0 lead at the start of the second half before André Schürrle halved the deficit just after the hour mark.
Coach Peter Stöger had said he wanted his team to "build on what we did in our positive phases in Leipzig."
Instead, for long periods, Dortmund delivered another exhibition of what sporting director Michael Zorc had criticized after the 1-1 draw with Augsburg as "administrator football" – unimaginative play lacking in creative ideas.
"We deserved to lose tonight, that simply wasn't good enough," said captain Marcel Schmelzer. "We can't allow that to happen at home – it's an absolute no-go. Now we've got a lot of making up to do."
'Test tube club'
Playing under the name "FC Salzburg" because UEFA forbids the use of sponsors in club names, the visitors, created in 2005 after Red Bull took over and rebranded the historic SV Austria Salzburg, were backed by 2,000 fans inside the Westfalenstadion - the largest away following in the club's short history.
In protest at their opponent's owners, hardcore Borussia Dortmund fans had announced their intention to boycott the second-leg in Salzburg, as they have done for their team's two away games against RB Leipzig, saying: "We cannot and will not accept test tube clubs from Salzburg and Leipzig who trample all over the values that we associate with football.”
On the Yellow Wall however, full again after last week's Monday night boycott against Augsburg, the protests were reduced to a few "anti-RB" banners and chants as fans watched their team fail to capitalize on their 63% first-half possession.
After his lightning start in a yellow shirt, Michy Batshuayi was quiet again. Marco Reus' passing was imprecise and Mario Götze also failed to make an impact.
Mahmoud Dahoud was the only Dortmund player to heed Stöger's wish and continue his positive form from the Bundesliga draw in Leipzig, but even his passes failed to break down a well-structured and combative Salzburg defense.
Encouraged by their hosts' lack of cutting edge, the eight-time Austrian champions eventually began to make their own advances as halftime approached. First, Roman Bürki saved from Hee-Chan Hwang but the ball fell to Munas Dabbur whose header was cleared off the line by Schmelzer.
In first-half injury time, they came even closer as Hwang's effort deflected off Omer Toprak and onto the post. The warning signs were there but if Stöger addressed them in the dressing room at half-time, there was no sign that his players had taken notice as Red Bull immediately attacked down the right hand side.
Berisha's brace, Schürrle responds
Hwang cut inside past Toprak who dragged the Korean back, the foul continuing into the box, leaving Slavko Vincic no choice but to point to the spot. Berisha slotted home and the 2,000 travelling fans had their goal.
Shortly later, they had two. Referee Vincic played on despite a clear foul from Stefan Lainer on Schmelzer before Hwang cut back for Berisha to smash the ball into the roof of Bürki's net.
Perhaps inspired by Hwang's success down the Salzburg right, Stöger reacted by bringing on his own wing wizard, Christian Pulisic replacing the ineffective Batshuayi and having an instant impact.
Reus immediately fed the American on the right hand side and Schürrle bundled home his cross in the middle. Game on.
Dortmund continued to look dangerous down the right-hand side. First, Maximilian Philipp, on for Götze, failed to make contact with Dahoud's cross which fell to Schürrle at the back post who shot over. Then Gonzalo Castro won a free-kick by the right-hand corner flag, from which Soktratis headed over – but it was the closest Dortmund came.
It's now over a month since Dortmund scored two goals or more away from home (the 3-2 win in Cologne) but that's what they now have to do in the Red Bull Arena in Salzburg next week – but without the backing of their boycotting supporters.