PARIS, Nov. 2 (Xinhua) -- World No. 1 Rafael Nadal is riding high at the Paris Masters as the Spaniard secured his place in last eight here on Thursday, while Argentina's Juan Martin del Potro marched on to keep his chances of reaching the ATP Finals alive.
Nadal and Pablo Cuevas of Uruguay held their serves in the first three games. Nadal almost let slide three break points in the fourth, but he regrouped to break for the first time after winning a hawk-eye challenge.
Leading 5-3 into the ninth game, Nadal saw his first serves slump, thus conceding three set points, while making a timely adjustment to take the first set 6-3.
In the second set, the two players forced a tie-break, where Cuevas won 7-5.
The Uruguayan injured his left thumb when returning a ball in the fifth game of the decider, while displaying his resistance to break for a one-game deficit.
Nadal broke immediately in the next game, before finding his place in last eight through a gritty 140-minute battle.
"Losing, not winning tough, is frustrating. You don't expect to win easy in big tournaments like these ones," admitted Nadal.
Nadal will face qualifier Filip Krajinovic in Friday's quarterfinals. The Serbian continued his surprising journey with a 6-2, 3-6, 6-1 victory over Frenchman Nicolas Mahut.
"He's playing well. He had a very successful season, winning a lot of challenges, and now he's playing well in ATP tour winning a lot of the matches.
"When you're winning a lot of matches, you're in a good run with good dynamic. So it's going to be a tough one," said Nadal.
Potro fared well in hard-court season, as he climbed from No. 47 to current No. 12 in the ATP Race To London Rankings, possessing a 20-4 record since the start of US Open.
After overcoming Robin Haase of the Netherlands 7-5, 6-4, Potro needs just one win from overtaking Spain's Pablo Carreno Busta, who currently sits on the final position for the Finals. A first ATP Masters 1000 title will guarantee Potro's position in London.
Next up against Potro is No. 9 seed John Isner, who upset Grigor Dimitrov in full sets. Potro shrugged off extra pressure ahead of this crucial clash.
"I take it as extra motivation to me. It's going to be a good battle next round trying to qualify for London," said Potro.
"I think I have two ways to take, one is London, one is my home and for vacations.
"Both ways are great to me, but of course I would love to reach London once again," he added.
Seventh-seeded David Goffin lost to home player Julien Benneteau 6-3 in both sets, while effectively clinching a spot in the Finals as home favorite Lucas Pouille fell to Jack Sock of the United States, leaving last berth up for grabs in Paris. Benneteau will next face third-seeded Marin Cilic.
"I would have preferred to have qualified by winning my match, and Lucas is a friend, but I am still so happy to have qualified," Goffin told ATP official website.
Sock's opponent will be Spain's Fernando Verdasco, who shocked No. 5 seed Dominic Thiem 6-4, 6-4.