Not about the quality of his play Friday, which fell below his usual standards at Roland Garros — for the second match in a row, he dropped a lethargic opening set before winning.
What really bothered the usually affable Nadal was the way the French Open's scheduling decisions, and the weather, combined to force him to now play on consecutive days, while his third-round opponent Saturday, Italy's Fabio Fognini, was "watching the TV in the locker room" on Friday.
"That's not fair," Nadal said, his arms crossed, his voice stern.
"This is not right," the seven-time champion in Paris said moments later, shaking his head and arching his left eyebrow.
What flustered Nadal, basically, was that his 4-6, 6-3, 6-3, 6-3 victory over Martin Klizan of Slovakia was supposed to be played Thursday but wound up being postponed because of rain — in part because it was the third match slated for its court.
The 27th-seeded Fognini's second-round victory win over Lukas Rosol, meanwhile, was No. 2 on its court and finished Thursday. Nadal's point: When there's rain in the forecast, everything possible should be done to ensure that two matches whose winners will face each other next should be completed on the same day.
Nadal also didn't like that while Fognini-Rosol followed one women's match — which, because they are best-of-three-sets, tend to be shorter than the men's best-of-five — on Thursday's program, Nadal-Klizan followed both a men's match and a women's match. His match should have taken priority on a day when showers made rescheduling likely, Nadal argued, because if women "have to play two days in a row, (it) is not a big deal."
Ana Ivanovic, the 2008 French Open women's champion, sided with Nadal on that point, saying men should "get more time to recover."
"Especially now, when he has to play day after day, I think he's right. They should play early," Ivanovic said after reaching the fourth round with a 6-3, 6-2 win against Virginie Razzano, the Frenchwoman who stunned Serena Williams in the first round last year.
Another complaint from Nadal: He said he was told by tournament officials they wanted to make sure Rosol got on court Thursday because, unlike Nadal, he also was in men's doubles.
"I am sorry, but that's a joke," Nadal said. "Why do you want to protect the player who has to play doubles? So I'm going to (sign up for) the doubles draw then, and I have the priority to play?"
A request for comment from tournament referee Stefan Fransson was declined by French tennis federation spokesman Christophe Proust, who said: "The federation does not want to respond. We don't want to get drawn into a controversy. It's not the first time that the scheduling has been criticized."
Now Nadal will need to win six matches over 10 days if he's going to be the first man to collect eight trophies at one Grand Slam tournament.
"Well, if I can win (Saturday), I'll have a day off, and that should be enough," the Spaniard said. "I don't think that will be a problem."
Once he got on a roll at his news conference, Nadal responded to a question about the men's tour calendar by bemoaning that there are too many tournaments players are required to enter. He also wished aloud that the ranking system were based on two years' worth of results instead of one, something he lobbied unsuccessfully for when he was a vice-president of the ATP Player Council.
All in all, the 11-time major champion's laments were the most interesting development on a day bereft of on-court drama for the top players — aside, perhaps, from that one-set stumble of his against the 35th-ranked Klizan.
Williams, seeking her first French Open title since 2002, extended her career-best winning streak to 27 matches by defeating Sorana Cirstea 6-0, 6-2 and has lost only six games through three rounds. Defending champion Maria Sharapova needed all of 15 minutes to finish off her straight-set win over Canada's Eugenie Bouchard in a rain-suspended second-round match. Two other past champions advanced: 2009's Svetlana Kuznetsova and 2010's Francesca Schiavone,
Roger Federer, whose record 17 Grand Slam titles include the 2009 French Open, lost serve in the very first game but not again, getting to the fourth round by eliminating No. 30 Julien Benneteau of France 6-3, 6-4, 7-5.
"I'm able to play quite aggressive at the moment," said Federer, who lost to Benneteau on an indoor hard court at Rotterdam, Netherlands, in February. "I don't know if I can keep that up. But the important thing is to keep the errors somewhat low because otherwise it's just silly aggressiveness. It has to be controlled aggression."
He now faces No. 15 Gilles Simon of France, who came back to beat No. 18 Sam Querrey of the United States 2-6, 6-3, 2-6, 7-6 (2), 6-2. That left No. 19 John Isner as the last U.S. man in the tournament after his 5-7, 6-7 (7), 6-3, 6-1, 8-6 win against Ryan Harrison.
Simon won the first two matches he played against Federer, but has lost the three since, including on clay at Rome a little more than two weeks ago.
"He really manoeuvred me around the court. He was playing well. He was very confident. He's always confident," Simon said through an interpreter. "Winning against him would just be awesome."
Klizan, the 2006 junior champion at Roland Garros, probably felt the same way before facing Nadal on a grey morning. Each began the day with only one loss for his French Open career; the difference is that Nadal's record was 53-1, Klizan's 2-1.
The match started a little past 11:15 a.m., so Nadal woke up bright and early at 7 a.m. and was at Roland Garros about 45 minutes later. He slumbered through the opening set, saying afterward: "I started the match probably with not the right intensity, with more doubts than usual."
Nadal lost only one set throughout the 2012 French Open, and that was in the final, so it was surprising to see him cede the first set of his opening match against 59th-ranked Daniel Brands, then do the same against Klizan.
But 18 minutes into the second set, Nadal led 4-0 and was on his way.
He promised that he will not let his thoughts about the scheduling affect him.
"Only thing that I can do is be positive, smile, and try to win my match," Nadal said, "and try to be ready for tomorrow."
Associated Press Writer Trung Latieule contributed to this report.
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