Barcelona, March 23 (IANS): Striker Luis Suarez's winner helped FC Barcelona defeat Real Madrid 2-1 to open up a four-point lead at the top of the La Liga football competition.

Suarez scored the winning goal in a tense and at times fractious match in which Real Madrid were the better side in the first 45 minutes, but ran out of steam after half time on Sunday, reports Xinhua.

There were very few surprises in the starting line-ups as Barcelona coach Luis Enrique decided against risking the fitness of midfielder Sergio Busquets, who began the game on the bench.

That once again saw defender Javier Mascherano push into midfield with Jeremy Mathieu partnering Gerard Pique in central defence.

Meanwhile, Luka Modric, Isco and Tony Kroos formed the trident in the Real midfield in a game which started with both sides looking sharp.

Striker Cristiano Ronaldo sent a volley against the Barcelona crossbar after 12 minutes following French forward Karim Benzema's cross.

Madrid were looking good, but it was Barcelona who opened the scoring when defender Pepe fouled Suarez. Forward Lionel Messi sent over the cross and Mathieu picked the perfect moment to score his first goal for the club with a powerful header past goalkeeper Iker Casillas.

Messi then teed up defender Jordi Alba to fire over and saw a free kick deflected for a corner, while both Suarez and Pepe saw yellow cards after exchanging fouls. Madrid drew level after the half hour as Ronaldo drilled past goalkeeper Claudio Bravo following more good work by Benzema, who had in turn been fed by the impressive Modric.

Tension was reaching boiling point and Ronaldo was then booked for diving, before Alba also picked a yellow card for dissent and winger Gareth Bale had a goal ruled offside following a tight off-side decision against Ronaldo.

Real were on top and Barcelona's goalkeeper Bravo had to save a Ronaldo drive before Bale missed a chance he should have scored with his left foot with the home side desperate for the half-time whistle.

The start of the second half saw both sides take stock of the situation. But Barcelona hit the fast forward button in the 56th minute when Suarez restored their lead with a right foot shot following good work from defender Dani Alves.

The goal was a body blow for Real, who struggled to react and Barcelona began to take control of a game in which yellow cards were produced at a regular rate.

Messi, Suarez, Neymar and Alba all had chances in the closing minutes. But Barcelona were unable to add to their lead.

Barcelona coach Enrique refused to believe his side had won the La Liga despite the win.

"I'm no friend of percentages or speculations. There are 10 games in which 30 points are left to play. We are where we want to be, but next game we have to play in Vigo (against Celta) which will be hard," he said after the match.

But he was delighted with the win.

"It is a win with a lot of merit, because Madrid are a great team. We are content and satisfied and we could have scored more goals... It' s the only disappointment I have from the game, but I realize Real Madrid could have scored more in the first half," he said.

Real coach Carlo Ancelotti believed his side had been better for much of the game, but had failed to take chances to win in the first 45 minutes.

"I will remember first half where we played well, solid in defence and good in attack, in the end we played too many long balls," he said.

"I don' t think it was a physical problem, but the last 30 minutes were not like the first half."

Despite the defeat, Ancelotti was positive about the performance.

"We have to carry on with this idea, the team has done well. But now we are 4 points behind Barcelona, the league is difficult."