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PARIS May 31 (Reuters) - Defending champion Rafa Nadal labelled the French Open schedule "a joke" and revealed he had struggled to motivate himself after reaching the third round with an unconvincing victory over Slovakian Martin Klizan on Friday.
Nadal, seeking his eighth Roland Garros title, looked ill at ease against fellow left-hander Klizan before securing a 4-6 6-3 6-3 6-3 on a cool, blustery day in Paris.
The 26-year-old had not struck a ball in anger since struggling past Germany's Daniel Brands on Monday and seemed rusty as he initially allowed the powerful Klizan to dictate the baseline exchanges.
He eventually found enough gears to avoid any real alarms but later said he was unhappy about falling a round behind his main rivals for the title because of Thursday's rain which meant his clash with Klizan was postponed.
"Yesterday I just warmed up for half an hour, so I've not played much tennis during three days," Nadal, who will now have to play a rested Fabio Fognini on Saturday, told reporters.
"I think everybody knows in this room that the schedule of yesterday was wrong."
Nadal's main gripe was that the tournament's schedulers put him down for the last match on Suzanne Lenglen court on Thursday, after a women's singles and men's singles, while Fognini only had to wait for a very quick women's match to finish.
Fognini polished off Lukas Rosol on Thursday while Nadal was left kicking his heels and the Spaniard faces a heavier schedule than his rivals if he is to retain his title.
"I cannot play third after men's and girls when our possible opponent plays second after girls. That's not fair," he said.
"Today I was playing almost three hours on court, and my opponent was watching the TV in the locker room.
"I can only smile and try to win my match and try to be ready for tomorrow. But that's not the right thing and I hope they accept the mistake.
"The excuse they told me was because Rosol had to play doubles. I am sorry, but that's a joke.
"Why do you want to protect the player who has to play doubles? So I'm going to write myself on the doubles draw then and I have the priority to play?"
Klizan, ranked 35th in the world, had obviously taken a leaf out of the German Brands's book with some heavy hitting from the baseline to unsettle Nadal who was strangely subdued early on.
"I don't think there was enough intensity, so it was rather predictable that the first set should go that way," Nadal said.
"I simply had to add intensity, increase my level of game, my attitude, and I found the motivation. In the first set I simply was not motivated enough."
A dreadful airy dropshot by Nadal in the seventh game was punished as Klizan earned the first break of the match and then he took his chance emphatically, serving out the set with the help of a booming second serve ace.
Nadal surged 4-0 ahead in the second but 23-year-old Klizan remained a threat and recovered one of the breaks of serve.
Third seed Nadal took the second set and moved a break ahead in the third but wobbled at 3-2 when Klizan earned two break points, only to squander his chance to draw level.
Klizan's challenge faded and Nadal, without looking totally convincing and carelessly dropping serve late in the fourth set, secured a clash with Fognini.
"He's a very serious player. He's already won matches. He's confident," he said. "I'm going to try and play better than I played today. I think I have to deliver a top performance." (Editing by Ed Osmond)