Who was the first #1 male tennis player never to have won a grand slam event?

Marcelo Rios is the only male tennis player to have been ranked number one in the world and never have won a Grand Slam tournament. The closest he came was a defeat in the Australian Open finals in 1998. He was defeated by Petr Korda who ironically tested positive for steroids a few months later. Rios became the first South American player to reach the global number-one spot. He was 22 at the time and played competitively until he was 28.

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