In this Feb. 2, 2011, file photo, Ronaldo of Brazil's Corinthians, front, goes for the ball followed by Gerardo Vallejo of Colombia's Deportes Tolima during a Copa Libertadores soccer match in Ibague, Colombia. Ronaldo said on Monday, Feb. 14, 2011, he is retiring from soccer because he can't stay fit anymore, ending a stellar 18-year career in which he thrived with Brazil and some of Europe's top clubs.
FILE - In this Jan. 26, 1997, file photo, Barcelona's Brazilian striker Ronaldo shows off his FIFA "World's best player" trophy to the crowd before the start of Barcelona's league match against Rayo Vallecano in Bracelona, Spain.
In this Jan. 26, 1997, file photo, Barcelona's Brazilian striker Ronaldo kisses the trophy.
In this Dec. 3, 1999, file photo, Brazilian soccer star Ronaldo smiles as he walks on crutches in the Orthopedic and Traumatology department at the Pitie-Salpetriere hospital in Paris, France.
In this April 11, 2004, file photo, Real Madrid's Brazilian striker Ronaldo grimaces after a tackle during a Spanish league soccer match against Osasuna at the Bernabeu stadium in Madrid, Spain.
In this June 30, 2002, file photo, Brazil's Ronaldo (9) beats Germany's goalie Oliver Kahn to score during the second half of the 2002 World Cup final in Yokohama, Japan.
In this March 11, 2007, file photo, AC Milan's Ronaldo of Brazil celebrates after scoring against Inter Milan during an Italian major league soccer match at the San Siro stadium in Milan, Italy.
Ronaldo, a 34-year-old striker, announced his retirement on Monday. The three-time FIFA Player of the Year was the top goal scorer in World Cup history.