Rafael Nadal wrecked Roger Federer's dreams of completing a Grand Slam of major titles by triumphing in a four-set epic to claim a third straight French Open crown.

For a second successive year, the world number one was denied by the Spaniard at the final hurdle at Roland Garros, second seed Nadal recording a 6-3 4-6 6-3 6-4 win in three hours 10 minutes on Court Philippe Chatrier.

Nadal, who also beat Federer in the 2005 semi-final here, becomes the first player since Bjorn Borg - who won four straight between 1978 and 1981 - to win the French Open three years on the trot.

And the 21-year-old king of clay keeps his extraordinary unbeaten streak at Roland Garros going - he is yet to be defeated at the Parisian grand slam since making his debut here in 2005.

Federer had his chances throughout the match, but a damning statistic of just one successful break in 17 attempts tells its own story.

Nadal, meanwhile, had a four-of-10 success rate on his break points and that ultimately was the difference.

Federer could at least celebrate taking a set off his rival, something Nadal's previous six opponents in this tournament had failed to do.

But the energy expended in winning the second set took its toll on the top seed, whose Roland Garros hoodoo continues.

People had been waiting for this clash since the tournament draw was made more than two weeks ago, and it did not disappoint.

Federer came into it boosted by last month's win over Nadal in the final of the Hamburg Masters, the Swiss' first victory over his great rival on clay.

He claimed he now knew the key to defeating the Spaniard on his favoured surface, and he dominated the 51-minute first set, especially on the Spaniard's serve. Somehow he lost it.

Federer had as many as 10 break points - two in the fourth game, five in the sixth and three in the eighth - but a mixture of his unforced errors and Nadal's gumption when it really mattered saved the Spaniard.

Unlike the Swiss, Nadal was clinical and took his only two break points of the set to nick it.

The first came in the seventh game when he struck at 40-0 up, Federer still at that time struggling to come to terms with his failure to break the previous game.

The second arrived in what proved to be the final game of the set, Federer slipping 40-30 down and then seeing a whipped forehand flash past him down the line.

Federer's first serve was at a worrying 38 per cent in that first set, but he still appeared the more dominant player and he demonstrated that in a second set that lasted almost an hour.

The first six games went with serve, Nadal wasting a break chance in the fourth.

But the Swiss turned it on in the seventh, going 40-0 up and finally unlocking Nadal's serve on the second of his break points, opening his body and sending an unreturnable fading forehand across court.

It was Federer's first break in 12 attempts and it gave him a deserved 4-3 lead in the set.

He threatened to undo all his good work in the eighth but Nadal wasted three break-point opportunities.

Federer should have levelled the match in a marathon ninth game, but he squandered four set points, taking his break-point success rate to just one of 16.

The Swiss, nevertheless, took the set on his serve the next game to draw all square.

A wounded Nadal bounced back, holding twice and breaking Federer to 15 to go 3-0 up.

For the first time in the contest, the world number one was struggling to make an impression on his opponent's serve and Nadal had no problems holding for the rest of the set to take it 6-3.

Nadal had wasted a set point in the eighth game when he sent an errant backhand wide, but on his third attempt - in the ninth - he landed with a cross-court forehand with heavy top spin to regain his set advantage.

Federer held the opening game of the fourth before squandering a break point in the second.

The match then took a decisive turn when Federer powered a forehand into the net when 40-30 down on his own serve, and Nadal had established a 2-1 lead with a break.

He was never to relinquish that cushion and his ability to avoid the unforced error started to take its toll on Federer.

Serving for the title at 5-3 up, Nadal went 30-0 up and a rapier-like forehand gave him three match points.

He needed just one, a long Federer forehand earning the Spaniard the title.

Nadal spared a thought for Federer after wrapping up the victory.

He said: "I'm sorry for Federer, he's a terrific player and a great competitor.

"The first set was very important, he had a lot of break points.

"It's just a dream to win here and I've got to keep working to get better and better.''

Federer added: "He put the youngsters to the sword here, Rafa Nadal is just awesome.''