Following the startling admission from people's favourite Andre Agassi that he took drugs during his glittering tennis career, we take a look at some of the biggest substance abuse scandals to have rocked sport.
Agassi stunned the tennis world last week when he admitted to taking crystal meth and then lying to cover up a failed drugs test in 1997.
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Ben Johnson
Johnson's world record-winning 100 metres performance in the 1988 Seoul Olympics was sport's first major and biggest drugs scandal.
The now vilified Canadian beat American sportsbook favourite Carl Lewis to the gold medal in a time of 9.79 seconds but was disqualified three days later in a blaze of publicity.
The two had traded insinuating insults in the build-up to the summer games.
Diego Maradona
The sight of Maradona celebrating a goal down the barrel of a camera with his eyes bulging and veins popping led to a drugs test at the 1994 World Cup.
The Argentina legend had already been banned for taking cocaine two years previously and was found to have taken a cocktail of drugs which led to his immediate expulsion from the competition.
Marion Jones
Jones won five gold medals at the 2000 Olympics but her fall from grace was completed in 2008 when she served six months in prison for perjury.
She was stripped of all of her medals following a testimony from her disgraced former husband CJ Hunter - an Olympic shot-putter - that she had used banned substances in conjunction with him in the lead-up to the games in Sydney.
Dwain Chambers
Once the great hope of British sprinting, Chambers' life came crashing down around him when he failed a drugs test in 2003.
Chambers became embroiled in the BALCO controversy which was behind the designer steroid THG and was banned from competing for two years and told he would never be allowed to race in the Olympics again.
Michelle Smith
Irish swimmer Smith took the 1996 Olympics by storm after coming from nowhere to win three golds and one bronze medal in Atlanta.
Several competitors openly spoke of their surprise at her overnight success and pointed to the past failed drugs test of her trainer husband, but Smith herself never failed a drugs test.
However, she was banned for four years in 1998 after being found to have tampered with a urine sample.