Roddick: knee injury
I have not fully recovered from my knee injury and I won't be able to compete.
Andy Roddick
Quotes of the week
Andy Roddick has withdrawn from the ATP World Tour Finals meaning Robin Soderling will make his debut at the season-ending tournament.
Roddick has admitted defeat in his efforts to recover from a left knee injury in time for the November 22-29 event at London's O2 Arena.
"I am really disappointed to miss the Barclays ATP World Tour Finals," Roddick said.
"I love playing in London and I've heard so many good things about the venue.
"However, I have not fully recovered from my knee injury and I won't be able to compete. One of my goals in 2010 will be to qualify for this event again."
Soderling was the first reserve for the eight-man showpiece and will now join Roger Federer, Rafael Nadal, Novak Djokovic, Andy Murray, Juan Martin del Potro, Nikolay Davydenko and Fernando Verdasco on the banks of the Thames.
The Swede hit the big time in spectacular fashion at the French Open this summer when he became the first player to beat Nadal at Roland Garros before finally losing to Federer in the final.
The 25-year-old took the momentum from his surprise run, winning the Swedish Open on home soil in Bastad and then reaching the quarter-finals of the US Open before climbing into the world's top 10 for the first time.
The draw for the two round-robin groups will be made on Wednesday morning.
France's Jo-Wilfried Tsonga is now first reserve.
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