PARIS — Maybe, just maybe, Rafael Nadal was a tad vulnerable, the thinking went before this French Open.
He had lost three times on his beloved red clay already this year, more defeats than he ever had on the surface before heading to Roland Garros.
Then came an admission, after the third round, that his back was bothering him and slowing his serves.
Well, leave it to the eight-time French Open champion's upcoming quarterfinal opponent — 2013 runner-up David Ferrer, one of the men who beat Nadal on clay this spring — to set the record straight.
"Rafael," Ferrer said, "is always the favorite."
Nadal looked the part in the fourth round Monday, when he won 18 points in a row during one stretch en route to beating 83rd-ranked Dusan Lajovic 6-1, 6-2, 6-1 for a record 32nd consecutive victory at the French Open. That broke his own mark of 31 and moved him closer to a fifth straight title in Paris.
The No. 1-ranked Nadal, now 63-1 for his career at the tournament, has won all 12 sets he has played in Paris in 2014, dropping a total of 23 games. He was asked whether he preferred a more taxing encounter by now.
"You never know what's better," he said. "But, in theory, the theory says that it's better (to) win like this than win longer matches."
And his back? The one that flummoxed him during a loss in the Australian Open final in January, and acted up Saturday, leading to an average first serve of 102 mph and top speed of 114? It didn't appear to be much of an issue against Lajovic: Nadal averaged 107 mph, with a high of 119.
"My back can be pretty unpredictable," said Nadal, who wore thick vertical strips of athletic tape under his shirt. "I'm not lying. It's totally unpredictable. I don't want to speak too much about it."
No. 7 Andy Murray beat No. 24 Fernando Verdasco 6-4, 7-5, 7-6 (7-3). In a wild third set, Verdasco held to get within 4-3 with an apparent service winner, but chair umpire Pascal Maria said that point should be replayed because a line judge called the ball out. Verdasco shouted "Are you kidding me?" and wanted a supervisor to intervene — until Murray conceded the point.
No. 28 Andrea Petkovic's 1-6, 6-2, 7-5 victory over 148th-ranked Kiki Bertens was the only three-setter for women, with 77 unforced errors and 14 service breaks. Afterward, Petkovic conducted a news conference sprinkled with references to Nietzsche, Sartre and Camus.
notable: Defending champions Bob and Mike Bryan lost in the men's doubles quarterfinals, 6-4, 6-2 to the 12th-seeded duo of Marcel Granollers and Marc Lopez. The Bryan twins, who were seeded No. 1, have failed to reach the final at the last three Grand Slam tournaments after winning four major titles in a row before that, starting at the 2012 U.S. Open. … Sloane Stephens lost to fourth-seeded Simona Halep 6-4, 6-3 in the fourth round, leaving no American singles players in the tournament. The 15th-seeded Stephens made 35 unforced errors, 10 more than Halep, and was broken six of nine times.