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Usain Bolt - Mystery resolved: the Olympic superstar retired from the track in 2017, and will captain the Soccer Aid World XI which will face Robbie Williams' England Aid XI, in Old Trafford.

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Usain Bolt - The announcement was part of a marketing stunt for the UNICEF charity match which will take place on June 10.

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Usain Bolt - The Jamaican loves soccer and this announcement caused a bit of a media stir, due to often stating his desire to play for Manchester United.

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Michael Jordan - Michael Jordan is considered by most to be the greatest in basketball history. He broke records and collected a ton of titles with the Chicago Bulls and American national team.

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Michael Jordan - In 1993 he announced his switch to baseball. He completed one season in the minor leagues with the Chicago White Sox, Birmingham Barons, and Scottsdale Scorpions. A year later he returned to the Bulls.

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Alex Zanardi - The Italian's story is one of adapting and overcoming. The driver was a well-known formula 1 driver, but suffered a serious accident on the track and had his two legs amputated.

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Alex Zanardi - Zanardi wouldn't be kept down. In less than two years he returned to racing in a specially adapted car. He later took up hand cycling and competed at the Paralympics.

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Alex Zanardi - At the Rio Olympics in 2016, aged 49, Zanardi won two gold medals and a silver, becoming the most successful paralympic handcycler.

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Paolo Maldini - A star for over 20 years with AC Milan and the Italian national team, in June 2017, aged 49, he debuted as a professional tennis player.

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Paolo Maldini - His first attempt wasn't too successful. Maldini and his doubles partner, Stefano Landonio, lost in the first round of the Milan Challenger.

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Fabien Barthez - The French keeper who won the World Cup in 1998 and starred for Olympique Marseille and Manchester United, hung up his gloves in 2007.

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Fabien Barthez - But he kept himself busy. In 2008 he began his Motorsport career, and has competed in competitions such as the 24 Hours of Le Mans.

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Andriy Shevchenko - One of Ukrainian soccer's biggest heroes, he starred for several big European teams, including AC Milan. He is currently the coach of the Ukrainian National Team.

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Andriy Shevchenko - He hung up his boots after Euro 2012, and made his debut as a professional golfer at the Challenge Tour the following year. He has continued to play golf as a hobby but is focused on his coaching career.

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Tim Wiese - Former German national team 'keeper and Werder Bremen cult hero, Wiese decided to become a wrestler.

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Tim Wiese - Looking somewhat unrecognizable from his goalkeeping days, Wiese joined the WWE and won his first match.

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Gabriel Batistuta - One of Argentina's greatest stars, the former target man spent time at Fiorentina and Roma. But chronic knee problems forced him to leave soccer in 2005.

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Gabriel Batistuta - He turned out to be a polo star, and in 2011, won a friendly tournament with Boca Juniors in Argentina. Unfortunately due to his knee problems he also had to leave the sport behind.

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Ronda Rousey - Once one of the stars of MMA, Rousey was actually a judoka first. Ronda competed in two Olympic games, and even won medals.

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Ronda Rousey - She swapped the mat for the octagon and became a UFC champion before recently joining the WWE.

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Paul Tracy - The Canadian driver divided his time between motorsports and professional mountain bike racing between 1994 and 1995.

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Paul Tracy - But he stuck with the racing track and has competed in CART, Champ Car World Series, and IndyCar Series.

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Brock Lesnar - The American fighter is a WWE champion and has fought in the UFC. He is known as 'The Beast Incarnate' due to his size and strength.

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Brock Lesnar - In 2004 he got tired of the WWE and left to play American Football, where he played in several games for the Minnesota Vikings. The following year, however, saw Lesnar return to professional wrestling.

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Jimmy Bullard - The ex-England star played for eight teams in a career that lasted from 1998 to 2012.

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Jimmy Bullard - He retired in 2012 due to recurring injuries. In 2013 he tried his luck at professional golf.

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Danny Ainge - One of the big stars of the Boston Celtics' 1980s team which won several NBA championships, Ainge had previously played baseball.

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Danny Ainge - He made his professional debut in the MLB with the Toronto Blue Jays in 1977.

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Tim Duncan - Duncan is now retired, but the former San Antonio Spurs was one of, if not the best, power forwards in NBA history.

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Tim Duncan - Before basketball, Duncan competed in swimming. He left the sport when the Olympic pool in his hometown in the US Virgin Islands was destroyed by a hurricane. Tim had to swim in the sea and was put off by sharks. Sounds fair.

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Ronda Rousey and Alex Zanardi -

Ronda Rousey and Alex Zanardi

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Ronda Rousey and Alex Zanardi -

Ronda Rousey and Alex Zanardi

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