Spain failed to break down Portugal in the first half Wednesday, leaving the teams at 0-0 at halftime in the European Championship semifinals.
With neither side taking risks, the goalkeepers were rarely tested in a scrappy, physical half.
Andres Iniesta had Spain's best chance in the 29th minute when he curled the ball just over after being set up by Xavi Hernandez. But Portugal's excellent organization and constant pressing disrupted Spain's passing game.
Cristiano Ronaldo looked sharp whenever he touched the ball and drilled a low shot wide of the post with Spain goalkeeper Iker Casillas struggling to cover.