Cracks are beginning to form within Hansi Flick's framework in Catalonia, but it's worth remembering this Barcelona team weren't meant to be in their current position.
Their recent form has been indifferent with fatigue starting to take hold, but Barca remain at the summit of La Liga and in an excellent position in the Champions League table.
The Catalonians will all but secure their place in the round of 16 with a fifth successive league phase victory on Wednesday, but Flick's team are travelling to a daunting environment where many fine outfits have succumbed in the past.
The German coach has settled on a preferred XI just a couple of months into his new job and wholesale changes are unlikely from Saturday's 2-2 draw at Real Betis. Here's how Barca could line up against Dortmund on Wednesday night.
Robert Lewandowski
Lewandowski is enjoying a resurgent season / Diego Souto/GettyImages
GK: Inaki Pena - It's hard to blame Pena for Barca's recent indifference and Flick won't be turning to veteran Wojciech Szczesny anytime soon.
RB: Jules Kounde - Kounde will be looking to end the year strong having endured a bit of a blip last month. The full-back teed up Robert Lewandowski's opener against Betis.
CB: Pau Cubarsi - The teenager will be looking over his shoulder given Ronald Araujo is back in the Barcelona squad. Xavi used the two together last season, but Cubarsi's current partner has been excellent this season.
CB: Inigo Martinez - It'll be interesting to see whom Flick opts to pair Araujo with once he returns to full fitness. With Barca's out-of-possession work faltering, they need superior recovery defenders in their backline. Martinez deserves to retain his place even with Araujo back in the fold.
LB: Alejandro Balde - Barca can ill-afford to lose Balde to injury again given what Gerard Martin and Hector Fort have produced on the pitch this season.
CM: Marc Casado - Casado's ascent has been rapid and he's quickly cemented himself as the lynchpin of Barcelona's midfield over Frenkie de Jong and Gavi.
CM: Pedri - The Spaniard looks in great shape and an undroppable figure in this Barca team despite his injury history. Flick offered Pedri respite by taking him off in the second half against Betis after the midfielder played a key role in the opening goal.
RW: Lamine Yamal - The teenager hasn't scored since Barca's emphatic win in El Clasico, but his influence has been distinct during their two most recent outings. Yamal recorded assists against both Mallorca and Betis.
AM: Fermin Lopez - Dani Olmo was hooked on the hour at the weekend and could sit out in midweek. Fermin entered the season in high spirits but has struggled for form since returning from injury. Flick requires more from the Olympic gold medalist, but he needs minutes.
LW: Raphinha - This may well be Raphinha's Barcelona. The Brazilian has taken his game to new heights this term and he's a shoo-in to start Wednesday's game after being withdrawn an hour into Saturday's draw.
ST: Robert Lewandowski - The striker scored his 23rd goal of the season at the weekend amid a resurgent campaign. Flick can turn to Ferran Torres, but Lewandowski will start against his former club on Wednesday.
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