Real Zaragoza gained the upper hand in their King's Cup quarter-final against Barcelona when defender Carlos Diogo headed in 12 minutes from time to earn his side a 1-0 win in the first leg at the Nou Camp on Wednesday.
The former Real Madrid player broke the deadlock in an absorbing and evenly matched encounter when he steered the ball past keeper Albert Jorquera after a corner.
Zaragoza knocked Barca out of the Cup at the same stage last season and also in 2004 when they went on to win the competition with victory over Real Madrid in the final.
Earlier, Getafe and Deportivo Coruna took a giant stride towards booking their places in on the last four with emphatic home wins in their first leg matches.
Bernd Schuster's Getafe were in unstoppable form as they overpowered Osasuna 3-0, while Depor produced a late burst to come from a goal down and defeat second division leaders Valladolid 4-1 at the Riazor.
Getafe striker Daniel Guiza, who scored both his side's goals in their 2-0 league win over Osasuna on Sunday, continued his rich run of recent form in front of goal when he headed in after a corner in the 11th minute.
Centre-back Alexis made it 2-0 when he rose above the Osasuna defence to head in from another corner six minutes before the break.
Latvia striker Verpakovskis took advantage of a dreadful error from Osasuna keeper Ricardo to side-foot into the empty net in the second half after the former Manchester United player let a ballooning cross slip through his fingers.
Deportivo struck twice in the closing minutes to end Valladolid's 21-match unbeaten run, although they were reduced to 10 men in injury time with the sending off of defender Alberto Lopo.