Switzerland's Roger Federer speaks during a press conference ahead of the Australian Open tennis championship in Melbourne, Australia, Saturday, Jan. 12, 2013. (AP Photo/Greg Baker)
TENNIS-OPEN-AUS
Jo-Wilfried Tsonga of France (C) and Roger Federer of Switzerland (R) take part in a Kids Day exhibition match ahead of the upcoming Australian Open tennis tournament in Melbourne on January 12, 2013. The first Grand Slam tennis tournament of the year is set to run from January 14 to 27. AFP PHOTO / MANAN VATSYAYANA IMAGE STRICTLY RESTRICTED TO EDITORIAL USE - STRICTLY NO COMMERCIAL USE (Photo credit should read MANAN VATSYAYANA/AFP/Getty Images)
TENNIS-OPEN-AUS
Roger Federer of Switzerland (R) chats with one of his support crew during a practice session for the upcoming Australian Open tennis tournament in Melbourne on January 12, 2013. The first Grand Slam tennis tournament of the year is set to run from January 14 to 27. AFP PHOTO / Paul CROCK IMAGE STRICTLY RESTRICTED TO EDITORIAL USE - STRICTLY NO COMMERCIAL USE (Photo credit should read PAUL CROCK/AFP/Getty Images)
TENNIS-OPEN-AUS
Roger Federer of Switzerland (R) warms up with cartoon character Sponge Bob during a Kids Day exhibition match in the lead-up to the Australian Open tennis tournament in Melbourne on January 12, 2013. The first Grand Slam tennis tournament of the year is set to run from January 14 to 27. AFP PHOTO / Paul CROCK IMAGE STRICTLY RESTRICTED TO EDITORIAL USE - STRICTLY NO COMMERCIAL USE (Photo credit should read PAUL CROCK/AFP/Getty Images)
TENNIS-OPEN-AUS
Roger Federer of Switzerland takes part in a practice session for the upcoming Australian Open tennis tournament in Melbourne on January 12, 2013. The first Grand Slam tennis tournament of the year is set to run from January 14 to 27. AFP PHOTO / Paul CROCK IMAGE STRICTLY RESTRICTED TO EDITORIAL USE - STRICTLY NO COMMERCIAL USE (Photo credit should read PAUL CROCK/AFP/Getty Images)
TENNIS-OPEN-AUS
Mirka Federer (R), the wife of Roger Federer of Switzerland, sits with their twins to watch her husband play in a Kids Day exhibition match in the lead-up to the Australian Open tennis tournament in Melbourne on January 12, 2013. The first Grand Slam tennis tournament of the year is set to run from January 14 to 27. AFP PHOTO / Paul CROCK IMAGE STRICTLY RESTRICTED TO EDITORIAL USE - STRICTLY NO COMMERCIAL USE (Photo credit should read PAUL CROCK/AFP/Getty Images)
2013 Australian Open Previews
MELBOURNE, AUSTRALIA - JANUARY 12: Roger Federer of Switzerland speaks to the media ahead of the 2013 Australian Open at Melbourne Park on January 12, 2013 in Melbourne, Australia. (Photo by Robert Prezioso/Getty Images)
2013 Australian Open Previews
MELBOURNE, AUSTRALIA - JANUARY 12: Roger Federer of Switzerland speaks to the media ahead of the 2013 Australian Open at Melbourne Park on January 12, 2013 in Melbourne, Australia. (Photo by Robert Prezioso/Getty Images)
TENNIS-OPEN-AUS
Roger Federer of Switzerland takes part in a practice session for the upcoming Australian Open tennis tournament in Melbourne on January 12, 2013. The first Grand Slam tennis tournament of the year is set to run from January 14 to 27. AFP PHOTO / Paul CROCK IMAGE STRICTLY RESTRICTED TO EDITORIAL USE - STRICTLY NO COMMERCIAL USE (Photo credit should read PAUL CROCK/AFP/Getty Images)
2013 Australian Open Previews
MELBOURNE, AUSTRALIA - JANUARY 12: Roger Federer of Switzerland speaks to the media ahead of the 2013 Australian Open at Melbourne Park on January 12, 2013 in Melbourne, Australia. (Photo by Robert Prezioso/Getty Images)
2013 Australian Open Previews
MELBOURNE, AUSTRALIA - JANUARY 12: Roger Federer of Switzerland speaks to the media ahead of the 2013 Australian Open at Melbourne Park on January 12, 2013 in Melbourne, Australia. (Photo by Robert Prezioso/Getty Images)
TENNIS-OPEN-AUS
Roger Federer of Switzerland takes part in a practice session for the upcoming Australian Open tennis tournament in Melbourne on January 12, 2013. The first Grand Slam tennis tournament of the year is set to run from January 14 to 27. AFP PHOTO / Paul CROCK IMAGE STRICTLY RESTRICTED TO EDITORIAL USE - STRICTLY NO COMMERCIAL USE (Photo credit should read PAUL CROCK/AFP/Getty Images)
TENNIS-OPEN-AUS
Roger Federer of Switzerland waves to the crowd as he takes a break during a practice session for the upcoming Australian Open tennis tournament in Melbourne on January 12, 2013. The first Grand Slam tennis tournament of the year is set to run from January 14 to 27. AFP PHOTO / Paul CROCK IMAGE STRICTLY RESTRICTED TO EDITORIAL USE - STRICTLY NO COMMERCIAL USE (Photo credit should read PAUL CROCK/AFP/Getty Images)
2013 Australian Open Previews
MELBOURNE, AUSTRALIA - JANUARY 12: (L-R) Victoria Azarenka, Jo-Wilfried Tsonga, Roger Federer, Novak Djokovic, Serena Williams and Ana Ivanovic pose with Nickelodeon characters during the Rod Laver Arena spectacular at Kids Tennis Day ahead of the 2013 Australian Open at Melbourne Park on January 12, 2013 in Melbourne, Australia. (Photo by Graham Denholm/Getty Images)
Switzerland's Roger Federer jokes with a cartoon character Sponge Bob Square Pants during an exhibition match during the Kids Tennis Day at Melbourne Park ahead of the Australian Open tennis championship in Melbourne, Australia, Saturday, Jan. 12, 2013. (AP Photo/Aaron Favila)
Mirka, wife of Switzerland's Roger Federer arrives on Rod Laver Arena with her daughters Myla and Charlene to watch an exhibition match during the Kids Tennis Day at Melbourne Park ahead of the Australian Open tennis championship in Melbourne, Australia, Saturday, Jan. 12, 2013.(AP Photo/Aaron Favila)
Switzerland's Roger Federer acts as a ball boy during an exhibition match at the Kids Tennis Day on Rod Laver Arena at Melbourne Park ahead of the Australian Open tennis championship in Melbourne, Australia, Saturday, Jan. 12, 2013. (AP Photo/Aaron Favila)
Mirka, right, wife of Switzerland's Roger Federer watches with her daughters Myla and Charlene and a unidentified woman a exhibition match during the Kids Tennis Day at Melbourne Park ahead of the Australian Open tennis championship in Melbourne, Australia, Saturday, Jan. 12, 2013.(AP Photo/Aaron Favila)
Switzerland's Roger Federer jokes with a cartoon character Sponge Bob Square Pants during an exhibition match during the Kids Tennis Day at Melbourne Park ahead of the Australian Open tennis championship in Melbourne, Australia, Saturday, Jan. 12, 2013. (AP Photo/Andy Wong)
Switzerland's Roger Federer and Victoria Azarenka of Belarus look as France's Jo-Wilfried Tsonga acts a s a ball ball during an exhibition match during the Kids Tennis Day at Melbourne Park ahead of the Australian Open tennis championship in Melbourne, Australia, Saturday, Jan. 12, 2013. (AP Photo/Andy Wong)
Switzerland's Roger Federer throws the ball along the court as he acts as a ball boy during an exhibition match during the Kids Tennis Day at Melbourne Park ahead of the Australian Open tennis championship in Melbourne, Australia, Saturday, Jan. 12, 2013. (AP Photo/Andy Wong)
Players from left, Victoria Azarenka of Belarus, France's Jo-Wilfried Tsonga, Switzerland's Roger Federer, Serbia's Novak Djokovic, Serena Williams of the US and Serbia's Ana Ivanoic pose for a group photo following an exhibition match on Rod Laver Arena during the Kids Tennis Day at Melbourne Park ahead of the Australian Open tennis championship in Melbourne, Australia, Saturday, Jan. 12, 2013. (AP Photo/Andy Wong)
France's Jo-Wilfried Tsonga, left, Switzerland's Roger Federer and Victoria Azarenka of Belarus play an exhibition match during the Kids Tennis Day at Melbourne Park ahead of the Australian Open tennis championship in Melbourne, Australia, Saturday, Jan. 12, 2013. (AP Photo/Andy Wong)
TENNIS-OPEN-AUS
Roger Federer of Switzerland hits a return during a practice session for the upcoming Australian Open tennis tournament in Melbourne on January 11, 2013. The first Grand Slam tennis tournament of the year is set to run from January 14 to 27. AFP PHOTO / Paul CROCK IMAGE STRICTLY RESTRICTED TO EDITORIAL USE - STRICTLY NO COMMERCIAL USE (Photo credit should read PAUL CROCK/AFP/Getty Images)
TENNIS-OPEN-AUS
Roger Federer of Switzerland serves during a practice session for the upcoming Australian Open tennis tournament in Melbourne on January 11, 2013. The first Grand Slam tennis tournament of the year is set to run from January 14 to 27. AFP PHOTO / Paul CROCK IMAGE STRICTLY RESTRICTED TO EDITORIAL USE - STRICTLY NO COMMERCIAL USE (Photo credit should read PAUL CROCK/AFP/Getty Images)
TENNIS-OPEN-AUS
Roger Federer of Switzerland (C) takes a break during a practice session for the upcoming Australian Open tennis tournament in Melbourne on January 11, 2013. The first Grand Slam tennis tournament of the year is set to run from January 14 to 27. AFP PHOTO / Paul CROCK IMAGE STRICTLY RESTRICTED TO EDITORIAL USE - STRICTLY NO COMMERCIAL USE (Photo credit should read PAUL CROCK/AFP/Getty Images)
TENNIS-OPEN-AUS
Roger Federer of Switzerland serves during a practice session for the upcoming Australian Open tennis tournament in Melbourne on January 11, 2013. The first Grand Slam tennis tournament of the year is set to run from January 14 to 27. AFP PHOTO / Paul CROCK IMAGE STRICTLY RESTRICTED TO EDITORIAL USE - STRICTLY NO COMMERCIAL USE (Photo credit should read PAUL CROCK/AFP/Getty Images)
2013 Australian Open Previews
MELBOURNE, AUSTRALIA - JANUARY 11: Roger Federer of Switzerland serves during a practice session ahead of the 2013 Australian Open at Melbourne Park on January 11, 2013 in Melbourne, Australia. (Photo by Vince Caligiuri/Getty Images)
TENNIS-OPEN-AUS
Roger Federer of Switzerland takes part in a practice session for the upcoming Australian Open tennis tournament in Melbourne on January 11, 2013. The first Grand Slam tennis tournament of the year is set to run from January 14 to 27. AFP PHOTO / Paul CROCK IMAGE STRICTLY RESTRICTED TO EDITORIAL USE - STRICTLY NO COMMERCIAL USE (Photo credit should read PAUL CROCK/AFP/Getty Images)
Switzerland's Roger Federer makes a backhand return during a practice session at Melbourne Park as he prepares for next week's Australian Open tennis championship in Melbourne, Australia, Friday, Jan. 11, 2013. (AP Photo/Mark Baker)
Switzerland's Roger Federer serves during a practice session at Melbourne Park as he prepares for next week's Australian Open tennis championship in Melbourne, Australia, Friday, Jan. 11, 2013. (AP Photo/Mark Baker)
Switzerland's Roger Federer, right, talks with to a training partner during a practice session at Melbourne Park as he prepares for next week's Australian Open tennis championship in Melbourne, Australia, Friday, Jan. 11, 2013. (AP Photo/Mark Baker)
Switzerland's Roger Federer serves during a practice session at Melbourne Park as he prepares for next week's Australian Open tennis championship in Melbourne, Australia, Friday, Jan. 11, 2013. (AP Photo/Mark Baker)
Switzerland's Roger Federer picks up a racket during a practice session at Melbourne Park as he prepares for next week's Australian Open tennis championship in Melbourne, Australia, Friday, Jan. 11, 2013. (AP Photo/Mark Baker)
Switzerland's Roger Federer serves during a practice session at Melbourne Park as he prepares for next week's Australian Open tennis championship in Melbourne, Australia, Friday, Jan. 11, 2013. (AP Photo/Mark Baker)
Switzerland's Roger Federer throws the ball in the air during a practice session at Melbourne Park as he prepares for next week's Australian Open tennis championship in Melbourne, Australia, Friday, Jan. 11, 2013. (AP Photo/Mark Baker)
Switzerland's Roger Federer serves during a practice session at Melbourne Park as he prepares for next week's Australian Open tennis championship in Melbourne, Australia, Friday, Jan. 11, 2013. (AP Photo/Mark Baker)
2013 Australian Open Previews
MELBOURNE, AUSTRALIA - JANUARY 08: Roger Federer of Switzerland plays a forehand during practice ahead of the 2013 Australian Open at Melbourne Park on January 8, 2013 in Melbourne, Australia. (Photo by Quinn Rooney/Getty Images)
2013 Australian Open Previews
MELBOURNE, AUSTRALIA - JANUARY 08: Roger Federer of Switzerland wears his Nike headband during practice ahead of the 2013 Australian Open at Melbourne Park on January 8, 2013 in Melbourne, Australia. (Photo by Michael Dodge/Getty Images)
2013 Australian Open Previews
MELBOURNE, AUSTRALIA - JANUARY 08: Roger Federer of Switzerland has a drink during practice ahead of the 2013 Australian Open at Melbourne Park on January 8, 2013 in Melbourne, Australia. (Photo by Quinn Rooney/Getty Images)
2013 Australian Open Previews
MELBOURNE, AUSTRALIA - JANUARY 08: Roger Federer of Switzerland plays a backhand during practice ahead of the 2013 Australian Open at Melbourne Park on January 8, 2013 in Melbourne, Australia. (Photo by Michael Dodge/Getty Images)
2013 Australian Open Previews
MELBOURNE, AUSTRALIA - JANUARY 08: Roger Federer of Switzerland plays a backhand during practice ahead of the 2013 Australian Open at Melbourne Park on January 8, 2013 in Melbourne, Australia. (Photo by Quinn Rooney/Getty Images)
Roger Federer
Switzerland's tennis player Roger Federer heads the ball as he plays an exhibition soccer-tennis game with Colombia's goalkeeper Farid Mondragon in Bogota, Colombia, Saturday, Dec. 15, 2012. (AP Photo/Fernando Vergara)
Roger Federer, Farid Mondragon
Switzerland's tennis player Roger Federer, left, returns the ball to Colombia's goalkeeper Farid Mondragon as they play an exhibition soccer-tennis match in Bogota, Colombia, Saturday, Dec. 15, 2012. (AP Photo/Fernando Vergara)
Roger Federer, Farid Mondragon
Switzerland's tennis player Roger Federer, left, returns the ball to Colombia's goalkeeper Farid Mondragon as they play an exhibition soccer-tennis match in Bogota, Colombia, Saturday, Dec. 15, 2012. (AP Photo/Fernando Vergara)
Roger Federer
Switzerland's tennis player Roger Federer returns the ball to a young player as he gives a tennis clinic in Bogota, Colombia, Saturday, Dec. 15, 2012. (AP Photo/Fernando Vergara)
TENNIS-COLOMBIA-FEDERER-CLINIC
Swiss tennis player Roger Federer gives the thumb up during a clinic in Bogota, Colombia, on December 15, 2012. AFP PHOTO/Eitan Abramovich (Photo credit should read EITAN ABRAMOVICH/AFP/Getty Images)
TENNIS-COLOMBIA-FEDERER-CLINIC
Swiss tennis player Roger Federer plays with a girl during a clinic in Bogota, Colombia, on December 15, 2012. AFP PHOTO/Eitan Abramovich (Photo credit should read EITAN ABRAMOVICH/AFP/Getty Images)
TENNIS-COLOMBIA-FEDERER-TSONGA-CLINIC
Swiss tennis player Roger Federer (L) and French tennis player French Jo-Wilfried Tsonga pose during a clinic in Bogota, Colombia, on December 15, 2012. AFP PHOTO/Eitan Abramovich (Photo credit should read EITAN ABRAMOVICH/AFP/Getty Images)
TENNIS-COLOMBIA-FEDERER-TSONGA-CLINIC
Swiss tennis player Roger Federer (L) and French tennis player French Jo-Wilfried Tsonga (R) sign autographes during a clinic in Bogota, Colombia, on December 15, 2012. AFP PHOTO/Eitan Abramovich (Photo credit should read EITAN ABRAMOVICH/AFP/Getty Images)
TENNIS-COLOMBIA-FEDERER-CLINIC
Swiss tennis player Roger Federer hugs a boy during a clinic in Bogota, Colombia, on December 15, 2012. AFP PHOTO/Eitan Abramovich (Photo credit should read EITAN ABRAMOVICH/AFP/Getty Images)
AP | Por Por JOCELYN GECKER Publicado: 12/01/2013 10:49 EST | Actualizado: 12/01/2013 11:41 EST