Espanyol v Barcelona. Again. For the third time in 11 days these local rivals do battle and that's exactly what the first two instalments of the hat-trick of fixtures have been.
A battle. Some would say a war. Two red cards for the Periquitos in last week's first leg and arguably one that was missed when Espanyol goalkeeper Paul Lopez deliberately stamped on Lionel Messi, an action missed by the match referee and his assistants.
Luis Suarez was subsequently banned for this game and another should Barca progress, for allegedly inciting the opposition in the tunnel after the game.
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It's sure to be explosive at Cornella El Prat on Wednesday evening so let's take a look at three things that could shape the outcome of this game.
The hosts have to come out and play in this one. They've no other option. Three goals down from the first leg, they have to score three to progress to the next round, and they won't achieve the same if they're content on kicking lumps out of their opponents rather than putting the ball in the net.
Playing at full throttle isn't something that Constantin Galca's side have been used to this season so it will be a new experience for all.
Arguably with the talented Real Madrid loanee Marco Asensio in situ, and Felipe Caicedo in the mood again, the hosts have every chance if they can score an early goal.
Luis Enrique, mindful that he has potentially another five games in January should his side win this one, will almost certainly rotate his squad.
Espanyol have to score three goals to be in with any chance whatsoever of winning the tie. Something they've done only once against Barcelona in 14 years.
It gives Lucho the perfect opportunity to tinker, allowing some senior members to have a well-earned evening off before the rigours of a home game against Athletic Bilbao at the weekend.
In so doing however, it does offer the hosts a tempting hint at the prize that awaits them.
Jeremy Mathieu has been simply awful when played this season and Marc Bartra has hardly covered himself in glory either.
At least Thomas Vermaelen and Aleix Vidal should be able to provide some riposte to the expected bombardment from the Periquitos.
Roberto to shine again?
With Andres Iniesta also rested, Sergi Roberto gets another chance to shine, this time wide left.
Although not a natural position for the youngster, he has played in six separate roles this season and has been equally good wherever he has been asked to fill in.
Against a rusty Jose Canas, in for the suspended Pape Diop, Roberto can wreak havoc alongside Neymar on that side of the pitch.
He could well prove to be the match winner for the Blaugrana.
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