On the field, Barca should have little problem sweeping aside an Olympiakos side without a point in the Champions League so far this season to consolidate their position atop Group D.
However, how Barca’s fans will react to a tumultuous few weeks of political tension in Catalonia is less predictable with the support split like the rest of society in the wealthy northeastern region of Spain.
“FC Barcelona will display a 45×46 metre banner at Camp Nou before kick-off Wednesday night emblazoned with the phrase ‘Dialogue, Respect, and Sport’ to call attention to the current situation in Catalonia,” Barca said in a statement on Tuesday.
“People come to the stadium to express themselves, to experience the game, to enjoy it and we hope that tomorrow people come to the stadium to enjoy watching us play,” added Barca coach Ernesto Valverde.
“If someone wants to demonstrate one way or another isn’t something that concerns us when we are preparing for a game.”
Chants in favour of independence are common at the Camp Nou from a section of the Barca fanbase, most notably in the 17th minute to mark the fall of Catalonia in the Spanish War of Succession in 1714.
Barca have also been repeatedly fined by UEFA for fans flying the Catalan ‘Estelada’ flag, which has become a symbol of the independence movement within Catalonia, at Champions League matches.
Leading Barca players such as Gerard Pique and Andres Iniesta called for politicians on both sides of the independence debate to negotiate in the wake of the October 1 referendum.
As Spanish riot police fired rubber bullets and seized ballot papers leaving 92 injured, among nearly 900 who sought medical attention that day, Barca beat Las Palmas 3-0 behind closed doors.
Club president Josep Maria Bartomeu insisted he tried to have the match abandoned, but instead settled for showing their opposition by playing the match in an empty 99,000-capacity Camp Nou.
– Confused standoff –
Yet, players have been less keen to position themselves on the confused political fallout in the past few weeks.
A standoff has ensued with Spanish Prime Minister Mariano Rajoy calling on Catalan leader Carles Puigdemont to clarify if he has declared independence for Catalonia on the basis of the referendum, deemed illegal by the Spanish government.
However, thousands of people took to the streets of Catalonia again on Tuesday after a judge ordered the detention of two separatist leaders Jordi Cuixart and Jordi Sanchez on Monday, reigniting the political touch paper.
Barca announced representatives of pro-independence citizens’ groups Omnium Cultural and the Catalan National Assembly, led by Cuixart and Sanchez respectively, will be invited to the game.
Barca’s first visit to Madrid since the escalation of the political divide to face Atletico Madrid on Saturday was expected to provoke a hostile welcome for the visitors.
However, other than the waving of more Spanish flags than normal at Atletico matches and some jeers for Pique, the match passed off peacefully.
“It was a great game, in a great atmosphere, in a great stadium,” said Valverde.
Despite a series of distractions on and off the field, including the loss of Neymar to Paris Saint-Germain and calls for Bartomeu to resign on top of the Catalonia crisis, Barca have started impressively under Valverde.
A run of nine straight wins in La Liga and the Champions League was ended on Saturday, but Barca are heavy favourites to get back to winning ways against one of Valverde’s former clubs.
Valverde won three league titles over two spells with the Greek giants, who have never won in 14 previous visits to Spain.