Substitute Cesc Fabregas converted the winning spot-kick, off the inside of the post, to set off wild celebrations from the Spanish players.Portugal Vs Spain Football Live Streaming 2012
"When I stepped up to take the penalty I said to the ball that we had to make history and that it shouldn't let me down," said an ecstatic Fabregas after Spain's 4-2 spot-kick victory following a 0-0 draw after extra time.
For Portugal, who had fought hard all night, questions will be asked why their top scorer Cristiano Ronaldo did not take a kick as they fell to their third semi-final defeat in four appearances at the stage.
Portugal had won their previous two penalty shootouts in major tournament matches.
Spain have now equaled West Germany's European record from the early 1970s by reaching three consecutive major tournament finals and victory in Kiev on Sunday would make them the first team to win three in a row.
But the watching Germans and Italians, who meet in Warsaw on Thursday, will have taken heart from a below-par performance from the Spaniards against a pressing Portugal team.
After a lively opening half hour, with both teams looking to get forward, the game gradually fizzled out and it was no surprise when the outcome had to be decided by penalties.
Xabi Alonso was first up for Spain and Portugal keeper Rui Patricio got down well to push his effort wide but then his opposite number Iker Casillas did likewise to save from Joao Moutinho.
The ball finally got in the net - after 120 minutes and two penalties - when Andres Iniesta scored with trademark composure but the contest turned when Portugal missed their fourth penalty when Bruno Alves struck the bar.
Alves had walked to take the third kick before being called away by Nani who converted his effort and that change only added to the mystery as to why Ronaldo was not used.
The Real Madrid winger was pencilled in for the fifth kick but after Fabregas' fortunate conversion off the posts, there was to be no fifth penalty.
"We had this plan and if it would have been 4-4 and he would taken the last penalty we would be talking in a different way," said Bento, who conceded there had been some confusion between Nani and Alves.
While the shootout provided most of the thrills, the two teams had suggested they might produce an exciting encounter from the outset.
Spain threatened twice in the opening half hour with Alvaro Arbeloa and Iniesta going close while at the other end Ronaldo fired a shot just past the post.
Ronaldo had a rare chance in the final minute of normal time but, after being fed by Raul Meireles after a fast counter-attack, he fired high and wide.
Patricio produced an excellent save to foil a close-range effort from Iniesta late in the first period of extra-time but it was no surprise when the contest had to be determined by penalties.
Portugal have never won a semi-final in a major tournament on foreign soil - their only triumph coming in 2004 when they hosted the tournament and were beaten by Greece in the final.
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