The Blaugrana secured a breathtaking 8-0 win over Real Murcia over two legs in their first Copa del Rey fixture of the season, with an aggregate 6-1 thumping of Celta Vigo helping Valverde's side reach the quarter-finals. The result ended a 29-match unbeaten streak for Barcelona in all competitions.
The second leg at the Santiago Bernabeu is on 24 January.
Lionel Messi's missed penalty handed Barcelona a surprise 1-0 loss at city rivals Espanyol in the first leg of the quarters of the King's Cup on Wednesday.
The Argentine failed to put Barca ahead when he took a spot kick, after a foul on Sergi Roberto, and was denied by goalkeeper Diego Lopez in the 62nd minute.
Espanyol's youth product Oscar Melendo scored the only goal of the match in the 88th minute.
Navarro then came close to giving the hosts the lead in the 83rd minute with a dipping free-kick that forced an excellent save from Jasper Cillessen, before five minutes later setting up the goal that gave Espanyol their first win over Barcelona in almost nine years.
It was Espanyol's first win against Barcelona at its RCDE Stadium. "We know already playing Espanyol at Cornella is hard". "The positive thing is that in a week we have a chance to rebound and advance".More news: Flu deaths continue to rise: Three more reported in Cuyahoga County
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"We knew [a defeat] was going to arrive at some point", Busquets said.
"We played with the same players in Vigo [against Celta] and I am happy with them", the coach said.
Melendo netted the victor with a low shot from the middle of the area after a well-timed pass by Marc Navarro.
The Catalan giants were dealt a blow 10 minutes into the second half when Paulinho was forced off due to an injury.
However, Sevilla grabbed a hugely fortunate and barely deserved equaliser seven minutes later when a speculative cross deflected off Atletico defender Lucas Hernandez and was then inexplicably pushed into his own net by keeper Miguel Angel Moya. We have to play at home, but they'll try to score. In the last five games, Espanyol has won three games, drawn one game and lost one game whereas Barcelona has won four games and drawn one game.
Valencia also scored two late goals in a 2-1 come-from-behind victory over 10-man Alaves. The visiting side went ahead through Ruben Sobrino in the 66th minute but Portugal worldwide Goncalo Guedes levelled for Valencia in the 73rd.