Barcelona capitalised on Real Madrid's profligacy to win the first El Clasico of the Primera Liga season 3-1 at the Santiago Bernabeu.
Real fail to build on dream start as champions prevail in Bernabeu
Barcelona capitalised on Real Madrid's profligacy to win the first El Clasico of the Primera Liga season 3-1 at the Santiago Bernabeu to move level with their arch rivals at the top of the table.
Real had come racing out of the blocks to take a first minute lead through Karim Benzema, but the normally prolific Cristiano Ronaldo endured a rare off day in front of goal.
Alexis Sanchez, who was chosen ahead of David Villa, drew Barca level on the half-hour before Xavi's freak goal put Pep Guardiola's side in front early in the second half.
Cesc Fabregas' header put the game beyond Real's reach as the title holders shrugged off the underdog tag that they had carried into the fixture.
Real enjoyed a dream start when taking the lead inside the opening 30 seconds following a shocking error from Barcelona goalkeeper Victor Valdes.
His pass out of defence was intercepted and, when Mesut Ozil's shot from the edge of the area was deflected into Benzema's path, the unmarked striker was able to prod home.
Menacing
Barcelona were quick to respond and Messi seized upon Sergio Ramos' slip to run menacingly at the Real defence before seeing a low shot superbly pushed away by Iker Casillas.
The Real keeper then punched away a Xavi free-kick before Ronaldo wasted a golden chance to increase the hosts' lead on 25 minutes.
Clever play from Benzema saw the France international's reverse pass find Ronaldo in space on the edge of the box, but he side-footed horribly wide when he should have hit the target.
The reigning champions were level on the half-hour mark after another penetrating run from Messi, who released Sanchez into space and the Chilean produced a crisp low finish beyond Casillas.
But before half-time, the Bernabeu faithful were baying for Messi's dismissal when he escaped a second yellow card following a foul on Xabi Alonso near the halfway line.
Fortunate
Valdes, who was enduring a shaky evening with the ball at his feet, comfortably saved a Ronaldo free-kick on 50 minutes before Barca took the lead in fortunate circumstances on 53 minutes.
The ball broke to Xavi 25 yards from goal and his well-struck volley appeared to be covered by Casillas only to take a wicked deflection off Marcelo and bounce into the net off the post.
Jose Mourinho introduced Kaka and Sami Khedira, but Barca came closest to another goal when Messi fired a low shot narrowly wide.
Ronaldo should have drawn his team level on 65 minutes when he was picked out unmarked by Xabi Alonso's cross, but the world's most expensive player could only steer his header wide of the goal.
And Ronaldo was made to pay for that miss just a minute later when Barca surged upfield and Dani Alves delivered a wonderful cross to the far post where Fabregas was racing in to head beyond Casillas.
Mourinho then threw on Gonzalo Higuain for fellow Argentina international Angel Di Maria, but Real were starting to cause problems for themselves and almost gifted Barca a fourth goal with four minutes to go.
Pepe's misplaced pass allowed Messi to slip in Iniesta, but his low shot from an angle was saved by Casillas and the Real keeper eventually gathered the ball after a scramble on the edge of the six-yard box.
