London, England -- (Sports Network) - Nikolay Davydenko had little trouble with Rafael Nadal at the ATP World Finals, defeating the Spaniard in straight sets in round-robin play at the season-ending tournament on Wednesday.

Davydenko, who claimed his first win of the event with a 6-1, 7-6 (7-4) decision, is still in contention to reach the semifinals, while Nadal dropped his second straight match and can no longer advance.

Earlier in the day, Robin Soderling made the most of his opportunity, as the Swede followed up a victory over Nadal with a triumph over Novak Djokovic.

Soderling, who gained entry into the exclusive eight-man field when American Andy Roddick withdrew because of injury, is 2-0 in Group B play. He posted a 7-6 (7-5), 6-1 win on Wednesday after toppling Nadal in straight sets to open round-robin play Monday.

It's been a breakthrough year for Soderling, who gained notoriety back in the spring when he knocked off Nadal in the fourth round of the French Open to deny the super Spaniard a chance at his fifth straight crown at Roland Garros. Soderling went on to the final at the clay court Grand Slam and lost to Roger Federer, who also beat the Swede in the quarterfinals at both Wimbledon and the U.S. Open.

Djokovic, the tournament's defending champion, fell to 1-1 in Group B. He beat Davydenko in his first match this week, but Wednesday's setback ended an 11- match winning streak. The Serb has won his past two tournaments, taking the Paris Masters two weeks ago after beating the great Federer on his home court in the final at the Swiss Indoors.