#1 Philipp Kohlschreiber (3-40)
With 40 cumulative losses against the trio of Federer (14), Nadal (15), and Djokovic (11), Philipp Kohlschreiber is one of 9 players to have lost at least 10 times against each member of men's tennis' famed trio.
Kohlschreiber has come up short in each of his 14 tour meetings with Federer, the most recent such occasion coming in the opening round at 2019 Dubai - where the Swiss maestro joined Jimmy Connors as the only players in the Open Era to win 100 career singles titles.
The German veteran's lone win against Nadal from 16 career clashes came in the quarterfinals on the grass of 2012 Halle. Meanwhile, he has beaten Djokovic twice in 13 meetings - 2009 Roland Garros third round and 2019 Indian Wells second round.
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