Shanghai - Juan Del Potro kept his hopes alive for an extended stay at the Masters Cup, winning a battle of first-time players 7-6 (7-4), 7-6 (7-5) over Jo-Wilfried Tsonga on Tuesday.

The Gold group clash between year-end rookies gave the Argentine a 1-1 record and saddled Australian Open finalist Tsonga from France with two defeats from as many matches.

"I'm in the Masters Cup, I want to be alive until the finals, if I can," he said.

Del Potro is trying to keep his mind off of the November 21-23 Davis Cup final against Spain where Argentina's chances of winning rose on Monday when world number one Rafael Nadal said he couldn't play for Spain due zo injury.

"For all tennis players, it's like a dream be here, and I have the chance to play, so I took it. But next week it will be another dream. We've never played the Davis Cup finals in Argentina.

"All the Argentina people wants to win the Davis Cup, so will be great for me also."

The 17 aces off the racket of Tsonga went for nought, with the Frenchman losing serve once per set in the defeat.

I'm very happy, I beat the winner of Paris," said Del Potro. "He has a lot of confidence, like me.

"I played the important points in the second set very well, that was the key to beat him."

Australian Open champion Novak Djokovic was bidding for a 2-0 record in group play as he faced four-time qualifier Nikolay Davydenko of Russia later.

Del Potro improved to 46-14 on the season while Tsonga dropped to 33-14.

Del Potro also took no notice of the split toenail which has hampered his game for more than two months as he notched the win.

The 20-year-old, who made a summer breakthrough with four consecutive titles, twice lost early breaks against Tsonga but managed to scratch through in the tiebreakers which decided a contest lasting just under two hours.

"He played better than me in the tiebreaks," said Tsonga. "I missed some easy balls. It is difficult for me because I lost the first match.

"That one was also very hard and very tight, and this one too. I'm disappointed but that is tennis and sport."

Del Potro posted his second career win against Tsonga after beating him prior to the US Open a year ago. (dpa)