#2 Rafael Nadal - 17*
In an era where Roger Federer was dominating the sport, Rafael Nadal came about as the only person who was challenging him and defeating him as well!
Nadal won his first Grand Slam in 2005, winning the French Open, thus becoming the first teenager to win a Grand Slam singles title since Pete Sampras won the 1990 US Open.
He is undoubtedly the best tennis player on clay ever, having won 11 French Open titles till date. Apart from this, he also has 2 Wimbledon titles, 3 US Open titles, and 1 Australian Open title to his name.
Much like Federer, he also went through a run of poor form in 2015 and 2016, however, he came back fighting in 2017 and has won three slams since.
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