Fourth-seeded Tomas Berdych lost his first match of the season on Monday, falling to Ivo Karlovic 7-6 (6), 7-6 (4) at the Qatar Open.
Karlovic served 25 aces and had 49 winners, while Berdych had eight aces and 28 winners. Neither player managed to break serve.
“It’s really hard to play someone who serves that well,” Berdych said. “It’s hard to find my rhythm on the court.”
Karlovic now leads Berdych 4-2 in head-to-head meetings. Berdych was the only top-10 player who did not win an ATP tour title last year.
Karlovic, a former top-15 player, finished the season last year ranked No. 77. He missed nearly two months in the spring when he became ill with spinal meningitis.
Eighth-seeded Fernando Verdasco of Spain won his first-round match 6-3, 6-3 over Filippo Volandri of Italy, while Gael Monfils of France beat Santiago Giraldo of Colombia 7-6 (1) 6-2.
Top-seeded Rafael Nadal was to play his opening singles match yesterday against Lukas Rosol of the Czech Republic, when No. 3 Andy Murray faces Qatari wild-card entry Mousa Shanan Zayed.
For Murray, it will be his first ATP singles match since having back surgery in September, although he teamed with Nenad Zimonjic of Serbia to defeat the German pairing of Daniel Brands and Florian Mayer in the doubles on Monday.
“I feel like I have recovered well from it [surgery], but it’s still a process,” said Murray, who lost an exhibition match against Jo-Wilfried Tsonga in Abu Dhabi last week. “You know, I don’t know exactly how I’m going to wake up tomorrow, but today was good in the match.”
World No. 1 Nadal has had new treatment on his troublesome knees, which could help him complete a full season on the ATP Tour for the first time since 2011.
The 27-year-old Spaniard also believes that it may prolong his career, but admits that the delay in restarting work during the off season has reduced his chances of regaining the Australian Open title in two weeks time.
Although Nadal would not say precisely what had been done to the semi-permanent injuries, he volunteered only that it was “different” and that he is hopeful for a healthier season this year. Nadal missed all of the second half of 2012 as well as the first Grand Slam of last year, in Australia, prompting many predictions that he would never be a world-beater again.
Though he proved these wrong, previous treatments have brought only temporary improvements, and Nadal is mindful that he has reached a crucial phase of his career if he is to fulfil his talent completely.
“I feel that this one really makes me feel more comfortable,” he said, when asked what the treatment was. “Because I don’t have pain like I had, no?”
“It is true that [last year] I played a lot of days with anti-inflammatories. But I was able to compete very well once I started. That was my goal and so I was very happy about everything,” he said.
Nadal is hoping anti-inflammatories will not be needed so much this year. In previous off-seasons he had plasma-rich platelets injected into his knees, but it seems likely that now he has had a different kind of injection.
“With this last treatment, I feel more comfortable on my knee during the rest of the day,” he said. “I feel that I can have a more normal life than I had during the last year and a half, because then I was playing tennis, and the rest of the time just relaxed.