Top seed and four time champion Roger Federer survived an opening scare at the 2009 Barclays ATP World Tour Finals with a hard fought three set win over Spaniard Fernando Verdasco to win the first Round Robin match of the Group A, bieng played here at the O2 Arena in London.

Federer made a shaky start to the match and lost his serve in the very first game. The Spanaird Verdasco then gallantly held all his serves and capitalised the single break to convert it into an opening set lead. The second set saw no breaks of serve and an improved Federer at all corners of the court as the Swiss finally broke the Spanish debutant in the 12th game to level the match one set a piece.

The decider turned out to be a one-man-show as Federer broke Verdasco twice to seal the victory in almost two hours of play with a 4-6, 7-5 6-1 scoreline.

With a the win, Federer boosted his chances of finishing the year as the World No.1 regardless of the outcome of the Grand Finale.

"I was down a set, and only the second set was I able to sort of get the ball into play, find my range, find my rhythm. The longer the match went, the more my belief was going up and his was going down. " Federer explained.

"After that, my fitness started going down. He also got confidence, and the match changed." said Verdasco.

After the match when asked about the venue, Federer said that he was impressed "I thought the crowds were great. The lighting is unique. We don't really see the crowd and the focus is very much on us. It's a bit unusual. It's not Wimbledon like, but still special obviously."

Earlier in the day, home favourite Andy Murray defied a spirited performance from current the U.S. Open champion Juan Martin Del Potro to win the first Round Robin match of the event after a three set tussle, lasting two hours and 10 minutes in play.

"When I got close to winning at the end of the match, the atmosphere was excellent," said an excited Murray. "That's going a make a big difference going into the next couple of matches."

"Me and Juan haven't played that much since the US Open. I kind of expected a little bit of a scrappy match maybe," added Murray. "He didn't start particularly well, but after 5-0, I thought the standard was very good. Played some great points. Obviously happy to get the win."

Tomorrow's matches will feature Six time Grand Slam champion Rafael Nadal up against Robin Soderling and last year's finalists Novak Djokovic and Nikolay Davydenko.