Copa del Rey holders Atletico Madrid hold a slender advantage over Athletic Bilbao in their quarter-final tie after Thursday's 1-0 win.
Atletico shaded an even first half at the Estadio Vicente Calderon, and took the lead just four minutes before the break as Diego Godin thumped a header home from Koke's superb right-wing cross.
Neither side were able to find the net in a dismal second half, although Atleti will be happy to have avoided conceding an away goal.
However, they will face a stern task in the Basque Country in next Wednesday's second leg, with Bilbao having won all but two of their games at the new San Mames since its opening in September.
Victory was just Atletico's second in five games, and coach Diego Simeone will undoubtedly be concerned about Diego Costa's ongoing woes in front of goal.
The forward has not found the net since the turn of the year, and saw chances pass him by yet again.
Both sides went close early on with Costa failing to turn home Koke's cross from the left from two yards out and Ander Herrera blazing over for the visitors.
Koke was central to everything good about Atletico's play and he provided a telling contribution, whipping a magnificent cross in that gave Godin the simple task of nodding past Bilbao goalkeeper Iago Herrerin.
Bilbao were neat in possession, but toothless in the final third against the hosts' fearsome defence. Oscar de Marcos looked to test Thibaut Courtois from 25 yards on the hour, but his driven effort bobbled wide.
Costa was visibly frustrated as half-time substitute Gabi failed to play him in on goal as Atletico launched a counter-attack.
Though the 25-year-old was unable to break his six-game scoring drought, it ultimately did not cost Simeone's side, who are well-placed to make the semi-finals.
|Lampard welcomes ´perfect´ NYCFC challenge|
|Shamrock Rovers 3 Progres Niederkorn 0: Waters at the double|
|Gerrard keen to emulate ´hero´ Beckham at Galaxy|
|UEFA Champions League Review: Red Imps make history, TNS breeze through|
|Ameobi extends Newcastle deal and heads for Cardiff|
|U.S. women celebrate World Cup victory with LA rally|
|Atletico agree Vietto deal|
|Silva appointed Olympiacos head coach|
|Presidential candidates unsure of Turan´s Barca switch|
|Toure keen to bounce back from ´disappointing´ campaign|
|El Salvador v Canada: Floro targets Gold Cup learning curve|
|Juve complete Zaza swoop|
|Costa Rica v Jamaica: Borges confident Wanchope´s men are ready|
|Marseille snare Sarr|
|Italy coach Conte to stand trial in match-fixing case|
|Castan keen to repay Roma´s faith|
|Rami thrilled to reunite with ´best coach´ Emery at Sevilla|
|Lusitans v West Ham: Tomkins seeks to silence minnows|
|Kagawa shines as Dortmund hit six in Japan|
|Alonso tips Gerrard for Galaxy glory|
|Firmino seeks self-improvement with Liverpool|
|Buffon bids farewell to Pirlo|
|Sterling named Europe´s ´most valuable´ young player|
|Casillas´ agent reveals Porto offer|
|Southampton bring in Martina|
|Dundee United accept Celtic´s Ciftci bid|
|McArthur pens new Palace deal|
|Bartomeu rules out Barca move for Pogba this year|
|Spurs have to be better now - Bentaleb|
|Milner expects central role|
|Micronesia thrashed again, this time 46-0|
|Marchisio: I cannot be Pirlo´s heir|
|Inter aiming for Champions League return - Icardi|
|UEFA Europa League Preview: Brondby and Slovan to protect handsome leads|
|Bentaleb pens new long-term deal at Tottenham|
|Barca agree Turan deal|
|FIFA bans Mayne-Nicholls|
|United States v Honduras: Klinsmann demands improvement ahead of Gold Cup opener|
|CONCACAF institutes extensive reforms in wake of FIFA corruption scandal|
|Mauri completes Milan move|
|City sign Turkey striker|
|Women´s World Cup final draws huge US TV ratings|
|My first Chelsea team better than current crop - Drogba|
|Bertrand set for lay-off after knee surgery|
|New five-year Juve deal for Marchisio|
|Allegri extends Juve contract|
|Koeman reiterates Alderweireld interest|
|Valencia bag Bakkali|
|New York City FC complete Pirlo capture|
|Panama v Haiti: Collat ready to challenge the best of CONCACAF|
|UEFA Champions League Preview: Harrison eyes TNS progression|
|FIFA sanctions Yemen for fielding ineligible player|
|Toulouse rubbish Ben Yedder exit reports|
|Mourinho ´knows what he´s doing´ with Falcao signing|
|Watford shell out club-record fee for Capoue|
|Braafheid signs Lazio extension|
|Nani finalises Fenerbahce move|
|Liverpool confirm O´Driscoll appointment|
|Liverpool have to start better - Lucas|
|USA simply too good - Sasaki|
|Portland Timbers 1 San Jose Earthquakes 0: Jewsbury wins it in stoppage time|
|No move yet for Van Persie|
|Lloyd wins Golden Ball, Silver Boot awards|
|Mascherano: I never grabbed Banega|
|Dunga requested Brazil not appeal Neymar´s suspension|
|United States 5 Japan 2: Lloyd stars with hat-trick|
|Fiorentina deny Inter criticism|
|Nani relishing Fenerbahce opportunity|