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who has won the most men's singles tennis titles
Roger Federer has won the most Grand Slam titles, most recently the Australian Open in 2018, with a total of 20.
what was Roger Federer's playing style
An elite athlete, Roger Federer is an all-court, all-around player known for his speed, fluid style of play, and exceptional shot making.
what is Roger Federer's equipment
Roger Federer plays with his signature Wilson Pro Staff RF97 Autograph racquet.

Question: what is the player's ranking
Self-contained rewrite: what is Roger Federer's ranking