Three days before facing Brendan Rodgers’ Super Hoops Barcelona crashed to a surprise 2-1 defeat from Alaves at the Nou Camp.
On the back of an international break Luis Enrique’s side are always vulnerable but even allowing for that it was a big surprise for the home fans to see their side lose at home to the newly promoted outfit.
After the match Enrique admitted: “We were fragile in defence and we will have to go over that. It’s an area where we’ve been strong in other years, but we also lacked fluidity and precision.
“The second goal, after another error by us, hit the group hard and did a lot of damage because it was a demonstration of our defensive fragility.
“It’s good for us to evaluate things and to recognise how difficult it is to compete in this league.”
Lionel Messi, Luis Suarez and Andres Iniesta all appeared as substitutes as Suarez attempted some squad rotation.
The defeat means that Barca drop down to fifth place, three points behind Real Madrid who maintained their 100% start to the La Liga season with a 5-2 win over Osasuna.
After the visit of Celtic on Tuesday Barca are away to Laganes before hosting Atletico Madrid a week on Wednesday, September 21.
Elsewhere in Champions League Group C Manchester City won 2-1 away to neighbours United while Borussia Monchengladbach lost 3-1 away to Freiburg.
