Rafael Nadal believes his sixth French Open title was the most special of them all.

The Spaniard defeated Roger Federer 7-5 7-6 (7/3) 5-7 6-1 on Sunday to equal Bjorn Borg's record of Roland Garros crowns and ensure he will be the world number one going into Wimbledon.

Nadal won last year's tournament without dropping a set but it was very different from the start this time as he battled back from two sets to one down against John Isner in round one and struggled through the rest of the first week.

The 25-year-old found his game when he needed to but was given a stern examination by great rival Federer, who showed he is far from a fading force.

Nadal, who will head to London on Monday for the AEGON Championships at Queen's Club, said: "To win this kind of title is always satisfying.

"But sometimes when you fight a lot to win, when you try your best in every moment to change the situation, it makes the title more special.

"For example, in 2008 I think I played better than ever, but I finished the tournament and I didn't feel that I won Roland Garros because I won in three sets every round."

Federer had lost three previous finals to Nadal at Roland Garros, the last of which in 2008 saw him win only four games, but his performance against Novak Djokovic on Friday was one of his best ever on clay and he came out fighting on Sunday.

Nadal looked nervy and in no time Federer was 5-2 in front. He even had a set point but narrowly missed with a drop shot, and that was the opening his opponent needed.

The Spaniard cranked up his ferocious forehand to break back and then made it five games in a row to win the first set.

The second set was a classic as Federer carried the disappointment into the early stages and had to fight for all he was worth not to trail by two breaks.

Gradually he rediscovered his early form and levelled at 4-4 only for Nadal to forge ahead again. Thunder rumbled around Roland Garros and, with the Spaniard at deuce having just missed a set point, the rain began to fall.

It was the first weather delay of the fortnight and it could not have come at a worse time, for Nadal anyway, because when they resumed only a few minutes later Federer saved a second set point before breaking back for 5-5.

He could not use that as momentum for the tie-break, though, with Nadal winning the first four points and going on to take it comfortably.

That looked set to be that, especially when Federer was broken to love to trail 4-2 in the third set. But the Swiss dug deep, played a brilliant game to hit straight back and then broke again before serving out the fourth set.

How he must have wished he had done that two hours earlier. Federer then had three chances to break again at the start of the fourth but they do not come mentally stronger than Nadal, and that would prove to be the third seed's last chance.

Nadal felt the start of the fourth set was the key moment, saying: "He was a little bit unlucky in the first set, and after that he came back fantastically well in the second.

"In the third I had 4-2 but I think he played very, very well from that moment to the beginning of the fourth. When Roger plays like this, the opponent cannot do anything sometimes.

"I just waited for my moment, tried to be there all the time, tried to put him in difficult situations. Saving the 0-40 was very important for me. That was a big turning point of the match."

Federer was back in a grand slam final for the first time since the Australian Open last year, and he was pleased with his display, although he knew the chances had been there for it to be so much better.

He said: "I'm the one that's playing with smaller margins, so obviously I'm always going to go through a few more ups and downs, whereas Rafa is content doing the one thing for the entire time.

"So it's always me who's going to dictate play and decide how the outcome is going to be. If I play well, I will most likely win, if I'm not playing so well, that's when he wins.

"But I thought Rafa played well. I think he dug deep to come back in the first set and get himself into the match. And also the second set.

"It was tough all the way through. I thought we played at a very high level and I was pretty happy with the way I played today.

"I don't have huge complaints but obviously there were some missed opportunities, because you'll always have plenty against him on clay. So if you lose, you always look at those.

"Overall I'm very happy about the tournament. Obviously you should be disappointed after losing in a grand slam final. I feel that a little bit today."