CURITIBA, Brazil (AP) -- Spain's attack is still struggling to turn dominating performances into goals, a worrying trend for the World Cup champions as they head to Brazil to defend their title.
Spain needed a pair of second-half goals from David Villa to get past El Salvador 2-0 Saturday in its final friendly match before the World Cup, a scoreline that didn't quite reflect just how Spain dominated its 68th-ranked opponent.
The world champions were barely troubled by El Salvador but still couldn't find more goals despite having striker Diego Costa available.
That could spell trouble for Spain, which is in a tough Group B where goal difference or goals scored could prove crucial in reaching the elimination stages.
''We lack consistency and precision inside the area,'' coach Vicente del Bosque said after the victory in Washington, ''but we were well-positioned on the field.
''We didn't have too many scoring chances but they were well organized in defense. But I'm not concerned if Spain plays this way because if we take the initiative ... I'm certain we'll find the necessary spaces to make that final pass.''
Spain opens its campaign on Friday against the Netherlands in a repeat of the 2010 final, which it won 1-0 after extra time. Group B also contains Chile and Australia, and every goal could be important for reaching the last 16. If teams are tied on points, goal difference is the first tiebreaker, followed by goals scored.
''I'm very happy with the role I've been given in the team, it's very clear,'' Villa said after extending his record tally to 58 goals for Spain. ''I don't know if I will start but I will work hard to try to.''
Costa showed he has overcome a right thigh muscle injury that limited his playing time over the last weeks of the season with Atletico Madrid, and forced him to come off early in the Champions League final. But he still couldn't convert in front of goal.
''The injury is still there in my head, but I felt good,'' Costa said. ''I'm just trying to play to my best ability. With every game I find myself synching better with my teammates.''
Del Bosque was certain Costa will be ready to play right from the start against the Dutch.
''It is true that he needs time to find his game after not playing for some time but I think he is ready to play in the World Cup,'' Del Bosque said. ''We're optimistic about our chances going into the competition.''
If Spain's attack continues to struggle, it can still likely depend on its defense for support. Spain has not conceded a goal in the knockout stages of the past two European Championships and the World Cup - a span of 10 games.
Fullback Jordi Alba appeared to pick up a knock to his ankle in Saturday's victory but Del Bosque was hopeful the Barcelona left back would be available for the opener in Salvador.
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