Valladolid have won only once in 30 visits to the Camp Nou stadium, but Louis van Gaal's side will not only have to win, but also convince one of the world's most demanding crowds that Wednesday's shock defeat by Dynamo Kiev in the Champions' League was not a sign of things to come.
The 4-0 loss at home dumped one of the pre-season favourites out of the European Cup. It also rattled the Spanish league leaders who just four days earlier had beaten Real Madrid 3-2 to take a seven-point lead over their arch rivals.
Few deny that a certain amount of luck accompanied that win, and that Barcelona's record of eight wins in nine games does not accurately reflect their present form. But even fewer people were prepared for Wednesday's result. Over half of the 60,000 spectators in the Camp Nou left before the end of the game, while those that were left cheered the visitors, and jeered several Barcelona players.
Van Gaal had already complained of the hostility of the crowd during the 3-2 win over Tenerife. And he will be well aware that former coach Bobby Robson was booed for using negative tactics during last season's 5-0 win over Rayo Vallecano.
So far the results - and in particular the win at Real Madrid - have kept Van Gaal afloat. But the swathe of injuries and suspensions which have hit Barcelona in the past few weeks will serve as little excuse for a manager who has one of Europe's strongest squads at his disposal.
The energy of the Spanish international Luis Enrique, who had been hit by a stomach infection, was badly missed against Dynamo, as were his opportunist goals. He is expected to take the place of the Brazilian midfielder Giovanni, who will sit out the game with a suspension handed out for making obscene gestures to Real Madrid fans.
But Van Gaal may not be too unhappy about losing another international. The Portuguese goalkeeper Vito Baia had a disastrous evening, and complained afterwards that he had not fully recovered from an injury that kept him out of action for two months. Baia's place will be taken by Ruud Hesp. The newly signed Dutchman has been one of the few success stories at Barcelona this season, and the signs are that Van Gaal will shortly be looking to clear out some veteran names from the days of Johan Cruyff, including Hristo Stoichkov.Reuse content