It was a good day for the top four men in world tennis as Rafael Nadal, Novak Dkjokovic, Roger Federer and Andy Murray all won their second round matches at the Madrid Open.

World number one Nadal extended his winning streak on clay to 35 matches after making easy work of Marcos Baghdatis with a  6-1 6-3 win, while world number two Djokovic extended his perfect record this season to 28 unbeaten matches with a 6-3 6-4 win against Kevin Anderson.

World number three, Roger Federer, had a tougher afternoon as he had to battle past Feliciano Lopez 7-6 (13-11) 6-7 (1-7) 7-6 (7-5). It was a nail-biting encounter as Lopez had a lead of 5-2 in the final set tie breaker before things turned when he missed a smash and Federer saved a match point.

 I thought he played well, said Federer. You could see he's been playing a lot of matches and he's confident, and I'm really relieved to have come through because it wasn't easy at all.

Watched by Real Madrid football star Cristiano Ronaldo, defending champion Nadal didn't need to face even a single break point as he converted his first match point to crush Baghdatis. The Spaniard has a tough test next though in the form of Juan Martin del Potro who thrashed Croatia's Marin Cilic 6-3 6-0.

Nadal was cautious about the match against Del Potro and said, It's one of those matches you can win or lose and anything could happen. I will try to play at my top level, aggressively and with more intensity. It's also true that I am coming into the match in good form and I will try to maintain that.

We will see who wins but the winner will take away a lot of confidence for the rest of the tournament I think.

Del Potro admitted it would be a tough evening for him. Obviously it will be one of the most difficult matches here on clay that there can be. I've never been capable of beating him on clay and let's see if it's tomorrow, but let me repeat that it's against the number one in the world and he's the best without a doubt on this type of surface.

Elsewhere, Djokovic continued his irrepressible form as he saw off South Africa's Anderson with ease. He will next face unseeded Spaniard Guillermo Garcia-Lopez and will look to extend his perfect run of the season.

With his unbeaten run, he is now part of an elite list with only John McEnroe in 1984 (42-match winning streak), Bjorn Borg in 1980 (33-match winning streak) and Ivan Lendl (29-match winning streak) above him.

The Serb , however, is not prioritizing the run. It's a great honour and very flattering to be part of that elite but it's not my priority. He said. I am just taking each match at a time and hoping I can win. It's kind of a surprise but I always believed that I have the quality to beat any player. I am a more mature player and I have more self-belief which is very important for this level.

Elsewhere, Andy Murray beat Gilles Simon 6-4 3-6 6-0.