PARIS - NOVEMBER 12: Radek Stepanek of Czech Republic in action during his match against Andy Murray of Great Britain during the ATP Masters Series at the Palais Omnisports De Paris-Bercy on...

...Roger Federer of Switzerland serves the ball during the men's singles second round match against Andy Murray of Great Britain during the Barclays ATP World Tour Finals at the O2 Arena on November...

Andy Murray, left, from Great Britain, shakes hands with Roger Federer, from Switzerland, after Murray upset No. 1...

PARIS - NOVEMBER 12: Andy Murray of Great Britain in action during his match against Radek Stepanek of Czech Republic during the...

Andy Murray of Britain reacts during his 4th round US Open match against Croatian Marin Cilic at the...

Andy Murray of Great Britain vies during a Davis Cup tennis Euro/Africa Group Zone One mens singles...

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LIVERPOOL, ENGLAND - SEPTEMBER 18: Andy Murray of Great Britain serves during the opening rubber of the Davis Cup tie between Great Britain...

Marin Cilic of Croatia serves to second-seeded Briton Andy Murray during their 4th round US Open match at the USTA Billie Jean King National Tennis Center...

NEW YORK - SEPTEMBER 08: Marin Cilic of Croatia celebrates match point against Andy Murray of Great Britain during day nine of the 2009 U.S. Open at the USTA Billie...

Andy Murray from the United Kingdom hits the ball against Marin Cilic from Croatia during their 4th round...

CINCINNATI - AUGUST 22: Andy Murray of Great Britain wipes sweat from his face in his semi final loss to Roger Federer...

Andy Murray of Great Britian returns against Paul Capdeville from Chile against during their 2nd round US Open...

NEW YORK - SEPTEMBER 01: Andy Murray of Great Britain returns a shot against Ernests Gulbis of Latvia during day two of the...

CINCINNATI, OH - AUGUST 22: Roger Federer of Switzerland pumps his fist following his match with Andy Murray of Great Britain during day six of the Western & Southern Financial Group Masters on August 22...

CINCINNATI, OH - AUGUST 22: Andy Murray of Great Britain returns a shot to Roger Federer of Switzerland during day six of the...