The 44-year-old has come under criticism for routinely tinkering with his starting XI since he took over from Gerardo Martino in the off-season.
With a last-32 first-leg trip to Segunda B outfit Huesca to come on Wednesday, the game offers the former Celta Vigo coach another chance to afford game-time to some of the fringe players in his squad.
Barca, who lost 2-1 in the final of this competition to fierce rivals Real Madrid back in April, could be without Jeremy Mathieu, after it was announced the Frenchman had come down with a virus on Monday.
And they will certainly be without Mathieu's fellow defender Thomas Vermaelen, whose Barca debut may not arrive until next season following confirmation his troublesome hamstring injury requires surgery.
Those absences will not stop Barca coming into the clash as clear favourites, although a visit to Huesca's Estadio El Alcoraz - with a capacity of less than 6,000 - could represent an unfamiliar experience.
Barca needed a last-gasp Sergio Busquets goal to defeat Valencia 1-0 in La Liga on Sunday - their fifth straight win in all competitions - although there was a sour end to proceedings when an object thrown from the Mestalla stands struck Lionel Messi on the head.
There was better news for the Argentinian on Monday, as he was announced as one of the three players in the running to receive the FIFA Ballon d'Or, alongside Real's Cristiano Ronaldo and Bayern Munich goalkeeper Manuel Neuer.
Wednesday's hosts saw their third-tier clash with Fuenlabrada on Saturday postponed due to a waterlogged pitch, but a statement on the club website on Monday assured fans that the playing area was now in perfect condition.
Luis Tevenet's side have certainly not had a straightforward passage en route to this meeting with the Catalan giants.
They needed extra time to overcome Toledo 1-0 in the first round, and they were staring elimination in the face at 2-0 down with three minutes to play against Villanovense in the second round.
Goals from David Morillas and Juanjo Camacho brought them level, before they advanced 4-3 on penalties.
In the third round they were on the brink of going out once again as they trailed Barakaldo by a goal to nil with four minutes to go, but Guillem Marti equalised before Inigo Ros struck the winner with a minute remaining in extra time.
Tevenet's men come into the clash in form, sitting third in Segunda B Group Two having won four consecutive matches, but an extension of that record on Wednesday would prove a major shock against a club that has won this competition a record 26 times.
