Nadal looking for extra zip

The world No 2 is lacking confidence as he prepares to face Nikolay Davydenko at the ATP World Tour Finals today.

Nadal has to win if he wants to close in on the gap between him and top-ranked Federer.

World No 2 Rafael Nadal is lacking confidence as he prepares to face Nikolay Davydenko at the ATP World Tour Finals in London today. The 23-year-old lost his opening match on Monday against Robin Soderling 6-4,6-4 and any hopes he harbours of closing the 945-point gap in in the rankings between himself and world No 1 Roger Federer hinge on this evening's clash at the O2 Arena in London. Davydenko may have lost to Novak Djokovic 3-6, 6-4, 7-5 in the first of his three round-robin matches - a repeat of last year's final - but Nadal knows it is he who must improve if he is to progress past the Russian and into the semi-finals.

"I think I didn't play really bad; I played OK, [but] my level right now is not No 1," said the Mallorcan following his defeat to Soderling on the medium-paced indoor court. "In the important moments, I didn't have the necessary calm, so I had a few mistakes. "He is a big player on this surface, so it is difficult. If you are not completely calm and playing very well in that moment, it's really difficult to win, and I didn't play in this way in those moments. I'm not far away from my best level, but I need more confidence."

Nadal was chasing his 400th win on the ATP tour, but Soderling is proving to be a thorn in his side, having finished his opponent's 31-match unbeaten run at the French Open earlier this season. "Sure, it feels better to beat the world No 2 than the No 200," said the Swede, who lost his first Grand Slam final to Federer at Roland Garros. "I always enjoy beating good players rather than lower ranked players. I managed to play really well on the important points, which is something you have to do if you want to beat the top guys. I've played a lot of big matches this year and played well, beaten a lot of good players, so I'm sure I've improved that part of my game."

Next up for the 25-year-old world No 9 is the Tour's most in-form player, Djokovic. The Serb has beaten both Federer and Nadal on his way to three titles from his past four tournaments, but is quick to play down his chances of success. "I'm very exhausted because of the long season," said Djokovic, who had to fight back for victory after losing the opening set against Davydenko. "He was a better player in the first two sets and maybe overall in the whole match. But when you have bad days, you still find a way to win - I think that's something that is great to have in your game.

"I wouldn't rate myself as a favourite [against Soderling] though. He's in great form so it's going to be a tough one." Davydenko was forced to call for a medic in the pivotal second set on Monday and said afterwards that he was suffering from the same breathing problems that have scarred his indoor season. "Some doctors say maybe asthma, some say maybe an allergy, some say bronchitis. If you see all the matches that I lose in three sets, that feeling has occurred."

The Argentine Juan Martin Del Potro secured his first win of the tournament by beating Spain's Fernando Verdasco in a tie-break last night. His 6-4, 3-6, 7-6 success ended a dramatic final set and came after Verdasco saved two match points. In the end, the tie-break was an anti-climax as Del Potro started with an ace and gave up only one point to take it 7-1. Verdaso is now almost certain to be eliminated in the group stage after two defeats, while del Potro is back in the hunt for a place in the knockout stage.

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