Cristiano Ronaldo's extra-time header gave Jose Mourinho his first trophy as Real Madrid coach as his side beat Barcelona 1-0 to win the Copa del Rey.A foul-ridden encounter was decided in the first period of extra-time when Ronaldo powered in his 42nd of the season from Angel di Maria's cross.Real had Iker Casillas to thank after the keeper denied Lionel Messi and Andres Iniesta with brilliant saves.Di Maria received a second yellow deep into extra-time but Real held on.Both Barca's best chances occured late in normal time with the cavaliers from Catalonia prevented from playing their normal game by the dogged and relentless chasing of Real.Los Blancos gave dangermen Messi, Iniesta, Xavi and David Villa little breathing space for much of the match at Valencia's Mestalla stadium.As soon as one of the quartet received the ball a Real duo would attempt to dispossess the ball either legally or illegally. The tactics made Barca look laboured.At no point in the first half did the potent Messi look like scoring his 50th this season, but it was a different tale at the other end for the other goal-machine on the pitch - Ronaldo.The Portugal midfielder, who scored his 41st this season with a penalty against the Catalan side last Saturday, had three chances to make it 42 in the opening half.The first was a shot from a tight angle which defender Javier Mascherano was forced to clear off the line before the £80m-man failed by fractions to get a connection on Mesut Ozil's dinked ball from six yards out.He came closest to scoring with his third chance of the half when Real's master of ceremonies, Ozil, sent his team-mate clear on the right who then forced a good low one-handed save from 35-year-old Jose Manuel Pinto.But shortly before the break, it was Ronaldo's compatriot Pepe, again playing in the centre, who came closest to ending the drought when his header from a Ozil delivery hit the inside of the post and flew to safety.