#1 Daniel Nestor
The recently retired Daniel Nestor is one of the greatest doubles players to have ever played the game. Nestor's career spanned 28 years, and during those years he notched up 1062 wins.
Nestor won a jaw-dropping 91 career doubles titles (second only to the Bryan twins). Significant among them are 8 Grand Slam Singles titles, the Olympic Gold Medal at the 2000 Sydney Olympic Games with Sebastien Lareau, and 5 ATP Finals trophies.
He tasted considerable success at the mixed doubles level too, winning 4 Grand Slam titles overall.
Nestor was the first player in tennis history to win every single Grand Slam and Masters Series event, the Year End ATP Finals Championships and Olympic gold medal at least once in his career.
From 1991 to 2018, Nestor played with 76 partners in doubles and 26 partners in mixed doubles. He holds the record for having won titles in more countries than any other player.
Nestor has won titles with 43 different partners, in 38 distinct countries.