Serena has won most number of matches at Grand Slams
Tennis player Serena Williams holds the all-time record for most number of victories in Grand Slam matches in tennis history. Serena has won 309 Grand Slam matches and surpassed Roger Federer's 307-win record earlier this month in the US Open. The American, who turned 35 on Monday, has lost only 43 Grand Slam matches and has an 88% winning rate.