(L-R) Pete Sampras, Roger Federer, Gael Monfils and Cedric Pioline of the Micromax Indian Aces share a moment during their match against the Singapore Slammers at the International Premier Tennis League (IPTL) in New Delhi, December 7, 2014. REUTERS/Adnan Abidi (INDIA - Tags: SPORT TENNIS) 

Pete Sampras of the Micromax Indian Aces hits a return a shot to Patrick Rafter of the Singapore Slammers during their men's singles match at the International Premier Tennis League (IPTL) in New Delhi, December 7, 2014. REUTERS/Adnan Abidi (INDIA - Tags: SPORT TENNIS) 

Rafael Nadal of Spain (R), Stanislas Wawrinka of Switzerland and Pete Sampras of the U.S. (C) pose during the prize ceremony after the men's singles final match at the Australian Open 2014 tennis tournament in Melbourne January 26, 2014. REUTERS/Bobby Yip (AUSTRALIA - Tags: SPORT TENNIS)

Tennis great Pete Sampras (bottom L) of the U.S. sits in the spectator stands ahead of the men's singles final match between Rafael Nadal of Spain and Stanislas Wawrinka of Switzerland at the Australian Open 2014 tennis tournament in Melbourne January 26, 2014. REUTERS/Jason Reed (AUSTRALIA - Tags: SPORT TENNIS)

Pete Sampras of the U.S. brings the Norman Brookes Challenge Cup at the Australian Open 2014 tennis tournament in Melbourne January 26, 2014. REUTERS/David Gray (AUSTRALIA - Tags: SPORT TENNIS)

Pete Sampras of the U.S. brings the Norman Brookes Challenge Cup at the Australian Open 2014 tennis tournament in Melbourne January 26, 2014. REUTERS/David Gray (AUSTRALIA - Tags: SPORT TENNIS)

Pete Sampras of the U.S. brings the Norman Brookes Challenge Cup at the Australian Open 2014 tennis tournament in Melbourne January 26, 2014. REUTERS/Jason Reed (AUSTRALIA - Tags: SPORT TENNIS)

Pete Sampras of the U.S. brings the Norman Brookes Challenge Cup at the Australian Open 2014 tennis tournament in Melbourne January 26, 2014. REUTERS/David Gray (AUSTRALIA - Tags: SPORT TENNIS)

Pete Sampras of the U.S. brings the Norman Brookes Challenge Cup
at the Australian Open 2014 tennis tournament in Melbourne January 26, 2014. REUTERS/Bobby Yip (AUSTRALIA - Tags: SPORT TENNIS)

Actor David Duchovny sits with his wife, actress Tea Leoni, as they watch former world number one Andre Agassi and 14-time grand slam champion Pete Sampras play their exhibition match at the BNP Paribas Showdown at Madison Square Garden in New York February 28, 2011. REUTERS/Mike Segar (UNITED STATES - Tags: SPORT TENNIS ENTERTAINMENT) 

Actor David Duchovny sits with his wife, actress Tea Leoni, as they watch former world number one Andre Agassi and 14-time grand slam champion Pete Sampras play their exhibition match at the BNP Paribas Showdown at Madison Square Garden in New York February 28, 2011. REUTERS/Mike Segar (UNITED STATES - Tags: SPORT TENNIS ENTERTAINMENT) 

Tennis legend Andre Agassi hits a return to fellow legend Pete Sampras during their exhibition match at the BNP Paribas Showdown at Madison Square Garden in New York February 28, 2011. REUTERS/Mike Segar (UNITED STATES - Tags: SPORT TENNIS) 

Tennis legends Pete Sampras (L) and Andre Agassi look up at a monitor playing highlights of one of their U.S. Open Final matches during their exhibition match at the BNP Paribas Showdown at Madison Square Garden in New York February 28, 2011. REUTERS/Mike Segar (UNITED STATES - Tags: SPORT TENNIS) 

Tennis legend Pete Sampras hits a return to fellow legend Andre Agassi during their exhibition match at the BNP Paribas Showdown at Madison Square Garden in New York February 28, 2011. REUTERS/Mike Segar (UNITED STATES - Tags: SPORT TENNIS) 

Tennis legend Andre Agassi reacts after winning a point against fellow legend Pete Sampras during their exhibition match at the BNP Paribas Showdown at Madison Square Garden in New York February 28, 2011. REUTERS/Mike Segar (UNITED STATES - Tags: SPORT TENNIS HEADSHOT) 

Tennis legend Pete Sampras reacts after winning the first set against fellow legend Andre Agassi during their exhibition match at the BNP Paribas Showdown at Madison Square Garden in New York February 28, 2011. REUTERS/Mike Segar (UNITED STATES - Tags: SPORT TENNIS) 

Tennis legend Pete Sampras (L) shakes hands with fellow legend Andre Agassi after Sampras won their exhibition match at the BNP Paribas Showdown at Madison Square Garden in New York February 28, 2011. REUTERS/Mike Segar (UNITED STATES - Tags: SPORT TENNIS) 

Tennis legend Pete Sampras reaches to hit a return to fellow legend Andre Agassi during their exhibition match at the BNP Paribas Showdown at Madison Square Garden in New York February 28, 2011. REUTERS/Mike Segar (UNITED STATES - Tags: SPORT TENNIS) 

Pete Sampras of the U.S. plays tennis at a meeting with children during part of the Andre Agassi Farewell Tour in Heredia, near San Jose September 18, 2010. Forty-year-old ex-U.S. tennis player Agassi, who retired in 2006, headlined a list of nominees for the International Tennis Hall of Fame following a sparkling career highlighted by eight grand slam titles and an Olympic gold medal. REUTERS/Juan Carlos Ulate (COSTA RICA - Tags: SPORT TENNIS) 

Former Russian tennis player Anna Kournikova poses after a news conference in Bogota August 20, 2010. Kournikova will participate in the Pete Sampras and Andre Agassi exhibition tour in Bogota. REUTERS/Fredy Builes (COLOMBIA - Tags: SPORT TENNIS) 

Former Russian tennis player Anna Kournikova attends a news conference in Bogota August 20, 2010. Kournikova will participate in the Pete Sampras and Andre Agassi exhibition tour in Bogota. REUTERS/Fredy Builes (COLOMBIA - Tags: SPORT TENNIS) 

Former Russian tennis player Anna Kournikova gestures during a news conference in Bogota August 20, 2010. Kournikova will take part in the Pete Sampras and Andre Agassi Tour Exhibition in Bogota on August 20. REUTERS/Jose Miguel Gomez (COLOMBIA - Tags: SPORT TENNIS HEADSHOT) 

Former Russian tennis player Anna Kournikova speaks during a news conference in Bogota August 20, 2010. Kournikova will take part in the Pete Sampras and Andre Agassi Tour Exhibition in Bogota on August 20. REUTERS/Jose Miguel Gomez (COLOMBIA - Tags: SPORT TENNIS HEADSHOT) 

Former Russian tennis player Anna Kournikova speaks during a news conference in Bogota August 20, 2010. Kournikova will take part in the Pete Sampras and Andre Agassi Tour Exhibition in Bogota on August 20. REUTERS/Jose Miguel Gomez (COLOMBIA - Tags: SPORT TENNIS HEADSHOT) 

Former Russian tennis player Anna Kournikova gestures during a news conference in Bogota August 20, 2010. Kournikova will take part in the Pete Sampras and Andre Agassi Tour Exhibition in Bogota on August 20. REUTERS/Jose Miguel Gomez (COLOMBIA - Tags: SPORT TENNIS HEADSHOT PROFILE) 

Former Russian tennis player Anna Kournikova speaks during a news conference in Bogota August 20, 2010. Kournikova will take part in the Pete Sampras and Andre Agassi Tour Exhibition in Bogota on August 20. REUTERS/Jose Miguel Gomez (COLOMBIA - Tags: SPORT TENNIS HEADSHOT) 

Fans wait for autographs from Andre Agassi of the U.S., Rafael Nadal of Spain, Roger Federer of Switzerland and Pete Sampras of the U.S. after their doubles exhibition match during the Hit for Haiti fund raiser event at the Indian Wells WTA and ATP tennis tournament in Indian Wells, California, March 12, 2010. REUTERS/Danny Moloshok (UNITED STATES - Tags: SPORT TENNIS IMAGES OF THE DAY) 

Andre Agassi of the U.S. (L) and Rafael Nadal of Spain talk during a break in play in an exhibition doubles match against Roger Federer of Switzerland and Pete Sampras of the U.S. during the Hit for Haiti fund raiser event at the Indian Wells WTA and ATP tennis tournament in Indian Wells, California, March 12, 2010. REUTERS/Danny Moloshok (UNITED STATES - Tags: SPORT TENNIS) 

Roger Federer of Switzerland (R) returns a shot as Pete Sampras of the U.S. (L) looks on during their doubles exhibition match against Andre Agassi of the U.S. and Rafael Nadal of Spain in the Hit for Haiti fund raiser event at the Indian Wells WTA and ATP tennis tournament in Indian Wells, California, March 12, 2010. REUTERS/Danny Moloshok (UNITED STATES - Tags: SPORT TENNIS) 

Andre Agassi of the U.S. acknowledges the crowd as he is introduced to play in a doubles exhibition match with Rafael Nadal of Spain, Roger Federer of Switzerland and Pete Sampras of the U.S. during the Hit for Haiti fund raiser event at the Indian Wells WTA and ATP tennis tournament in Indian Wells, California, March 12, 2010. REUTERS/Danny Moloshok (UNITED STATES - Tags: SPORT TENNIS) 

Andre Agassi of the U.S. (L) embraces Rafael Nadal of Spain before their doubles exhibition match against Roger Federer of Switzerland and Pete Sampras of the U.S. during the Hit for Haiti fund raiser event at the Indian Wells WTA and ATP tennis tournament in Indian Wells, California, March 12, 2010. REUTERS/Danny Moloshok (UNITED STATES - Tags: SPORT TENNIS) 

Andre Agassi of the U.S. pulls out his pockets while bantering with Pete Sampras of the U.S. During their a doubles exhibition match with Rafael Nadal of Spain and Roger Federer of Switzerland during the Hit for Haiti fund raiser event at the Indian Wells WTA and ATP tennis tournament in Indian Wells, California, March 12, 2010. REUTERS/Danny Moloshok (UNITED STATES - Tags: SPORT TENNIS) 

Andre Agassi of the U.S. rolls up his pants as he plays in a doubles exhibition match with Rafael Nadal of Spain, Roger Federer of Switzerland and Pete Sampras of the U.S. during the Hit for Haiti fund raiser event at the Indian Wells WTA and ATP tennis tournament in Indian Wells, California, March 12, 2010. REUTERS/Danny Moloshok (UNITED STATES - Tags: SPORT TENNIS) 

Roger Federer of Switzerland (R) and Pete Sampras of the U.S. (L) smile together on the court as they play against Andre Agassi of the U.S. and Rafael Nadal of Spain during their doubles exhibition doubles in the Hit for Haiti fund raiser event at the Indian Wells WTA and ATP tennis tournament in Indian Wells, California, March 12, 2010. REUTERS/Danny Moloshok (UNITED STATES - Tags: SPORT TENNIS) 

Andre Agassi (L) of the U.S. and Rafael Nadal of Spain smile together on the court as they play an exhibition doubles match against Roger Federer of Switzerland and Pete Sampras of the U.S. during the Hit for Haiti fund raiser event at the Indian Wells WTA and ATP tennis tournament in Indian Wells, California, March 12, 2010. REUTERS/Danny Moloshok (UNITED STATES - Tags: SPORT TENNIS DISASTER) 

Roger Federer (R) of Switzerland and Pete Sampras of the U.S. celebrate after winning a point against Andre Agassi of the U.S. and Rafael Nadal of Spain during their doubles exhibition match for the Hit for Haiti fund raiser event at the Indian Wells WTA and ATP tennis tournament in Indian Wells, California, March 12, 2010. REUTERS/Danny Moloshok (UNITED STATES - Tags: SPORT TENNIS) 

Switzerland's Roger Federer kisses the winner's trophy after winning the men's singles final against Australia's Mark Philippoussis at the Wimbledon Tennis Championships in London, in this July 6, 2003 file photo. After winning Wimbledon in 2003 Switzerland's Roger Federer spent the rest of the decade ripping up the record books, winning a further 14 grand slam titles to surpass the total of Pete Sampras who dominated the 1990s. In 2009 he reached every grand slam final and won the French Open for the first time. Picture taken July 6, 2003. To match feature -DECADE/ REUTERS/
Jeff J Mitchell (UNITED KINGDOM - Tags: SPORT TENNIS) 

Hong Kong actor Aaron Kwok (C) poses with Andre Agassi (L) of the U.S. and compatriot Pete Sampras before their exhibition tennis match at Venetian Macao in Macau October 25, 2009. REUTERS/Bobby Yip (CHINA SPORT TENNIS ENTERTAINMENT) 

Andre Agassi (L) of the U.S. greets compatriot Pete Sampras after their exhibition tennis match at Venetian Macao in Macau October 25, 2009. REUTERS/Bobby Yip (CHINA SPORT TENNIS) 

Andre Agassi (L) of the U.S. chats with compatriot Pete Sampras during an exhibition tennis match at Venetian Macao in Macau October 25, 2009. REUTERS/Bobby Yip (CHINA SPORT TENNIS) 

Pete Sampras of the U.S. acknowledges spectators before an exhibition tennis match against compatriot Andre Agassi at Venetian Macao in Macau October 25, 2009. REUTERS/Bobby Yip (CHINA SPORT TENNIS) 

Pete Sampras of the U.S. eyes the ball during an exhibition tennis match against compatriot Andre Agassi at Venetian Macao in Macau October 25, 2009. REUTERS/Bobby Yip (CHINA SPORT TENNIS) 

Andre Agassi of the U.S. prepares to serve during his tennis exhibition match against compatriot Pete Sampras at Venetian Macao in Macau October 25, 2009. REUTERS/Bobby Yip (CHINA SPORT TENNIS) 

Andre Agassi of the U.S. looks on during an exhibition tennis match against compatriot Pete Sampras at Venetian Macao in Macau October 25, 2009. REUTERS/Bobby Yip (CHINA SPORT TENNIS) 

Andre Agassi of the U.S. returns applause from spectators after his exhibition tennis match against compatriot Pete Sampras at Venetian Macao in Macau October 25, 2009. REUTERS/Bobby Yip (CHINA SPORT TENNIS) 

Pete Sampras of the U.S. reacts during an exhibition tennis match against compatriot Andre Agassi at Venetian Macao in Macau October 25, 2009. REUTERS/Bobby Yip (CHINA SPORT TENNIS) 

Andre Agassi of the U.S. reacts during his exhibition tennis match against compatriot Pete Sampras at Venetian Macao in Macau October 25, 2009. REUTERS/Bobby Yip (CHINA SPORT TENNIS) 

Andre Agassi of the U.S. returns a shot during an exhibition tennis match against compatriot Pete Sampras at Venetian Macao in Macau October 25, 2009. REUTERS/Bobby Yip (CHINA SPORT TENNIS) 

Pete Sampras of the U.S. reacts during an exhibition tennis match against compatriot Andre Agassi at Venetian Macao in Macau October 25, 2009. REUTERS/Bobby Yip (CHINA SPORT TENNIS) 

Seven-times Wimbledon Champion, Pete Sampras (FRONT R), his wife Bridgette (C) and the Governor of the Bank of England, Mervyn King (L), sit on Centre Court to watch the Gentlemen's Singles finals match between Andy Roddick of the U.S. and Roger Federer of Switzerland at the Wimbledon tennis championships in London, July 5, 2009. REUTERS/Stefan Wermuth (BRITAIN SPORT TENNIS) 

Seven-times Wimbledon champion Pete Sampras stands on Centre Court to watch the presentation after the Gentlemen's Singles finals match in which Roger Federer of Switzerland defeated Andy Roddick of the U.S. at the Wimbledon tennis championships in London, July 5, 2009. REUTERS/Stefan Wermuth (BRITAIN SPORT TENNIS) 

Seven-times Wimbledon champion Pete Sampras and his wife Bridgette sit on Centre Court to watch the Gentlemen's Singles finals match between Andy Roddick of the U.S. and Roger Federer of Switzerland at the Wimbledon tennis championships in London, July 5, 2009. REUTERS/Stefan Wermuth (BRITAIN SPORT TENNIS) 

Seven-times Wimbledon champion Pete Sampras sits on Centre Court to watch the Gentlemen's Singles finals match between Andy Roddick of the U.S. and Roger Federer of Switzerland at the Wimbledon tennis championships in London, July 5, 2009. REUTERS/Stefan Wermuth (BRITAIN SPORT TENNIS) 

Retired tennis player Pete Sampras demonstrates the Electronic Arts video game Grand Slam Tennis for Wii Fit platform, during a media event, before the opening day of the Electronic Entertainment Expo, or E3, at the Orpheum theatre in Los Angeles June 1, 2009. The convention runs from June 2-4. REUTERS/Mario Anzuoni (UNITED STATES ENTERTAINMENT BUSINESS SPORT) 

Retired tennis player Pete Sampras demonstrates the Electronic Arts video game Grand Slam Tennis for Wii Fit platform, during a media event, before the opening day of the Electronic Entertainment Expo, or E3, at the Orpheum theatre in Los Angeles June 1, 2009. The convention runs from June 2-4. REUTERS/Mario Anzuoni (UNITED STATES ENTERTAINMENT BUSINESS SPORT) 

Retired tennis player Pete Sampras demonstrates the Electronic Arts video game Grand Slam Tennis for Wii Fit platform, during a media event, before the opening day of the Electronic Entertainment Expo, or E3, at the Orpheum theatre in Los Angeles June 1, 2009. The convention runs from June 2-4. REUTERS/Mario Anzuoni (UNITED STATES ENTERTAINMENT BUSINESS SPORT) 

Tennis player Pete Sampras waves as he arrives to demonstrate the Electronic Arts video game Grand Slam Tennis for Wii Fit platform, during a media event, before the opening day of the Electronic Entertainment Expo, or E3, at the Orpheum theatre in Los Angeles June 1, 2009. The convention runs from June 2-4. REUTERS/Mario Anzuoni (UNITED STATES ENTERTAINMENT BUSINESS SPORT) 

Peter Moore (R), President of Electronic Arts Sports, demonstrates the Electronic Arts video game Grand Slam Tennis for Wii Fit platform, as tennis player Pete Sampras pretends to tap him, during a media event before the opening day of the Electronic Entertainment Expo, or E3, at the Orpheum theatre in Los Angeles June 1, 2009. The convention runs from June 2-4. REUTERS/Mario Anzuoni (UNITED STATES ENTERTAINMENT BUSINESS SPORT) 

Former tennis star Pete Sampras watches the Los Angeles Lakers play the Houston Rockets during Game 2 of their NBA Western Conference semi-final basketball playoff game in Los Angeles May 6, 2009. REUTERS/Lucy Nicholson (UNITED STATES SPORT BASKETBALL TENNIS) 

Pete Sampras of the US kisses the trophy after defeating Australia's Pat Rafter in the men's final at Wimbledon in this July 9, 2000 file photo. Sampras, the 14-times grand slam champion, is appearing in the final seniors tour event of the year, having recently rekindled his passion for the sport he dominated in the 1990s. The American's vise-like grip on tennis was at its most destructive in London and especially Wimbledon, where he chalked up seven major titles between 1993-2000. To match feature TENNIS/SAMPRAS REUTERS/Kieran Doherty/Files (BRITAIN)