#4 Potito Starace (Italy)
Potito Starace has come up short in all 13 matches against Federer and Nadal.
The Italian has met Federer on seven occasions - once at a Grand Slam (2007 Roland Garros), twice at Masters 1000 tournaments, once in an ATP 500 tournament, twice at an ATP 250 tournament and once in the Davis Cup (2009 Playoffs). He has managed to take a set off the illustrious Swiss only twice.
Against Nadal, Starace won a set in five matches - once at a Masters 1000 tournament (2008 Hamburg), twice at ATP 500 tournaments (2007-08 Barcelona), twice at ATP 250 tournaments and once at the Olympics (2008 Beijing). But he has lost all six times he has faced the Spaniard.
#3 Diego Schwartzman (Argentina)
The 14th-ranked Diego Schwartzman is the highest ranked player to play Federer and Nadal on at least 10 occasions (13) without winning even once.
The diminutive Argentinian has been a tough competitor for Nadal, taking a set off the Spaniard twice (2018 Roland Garros quarterfinals and 2018 Australian Open fourth round). But he has fallen short on all nine occasions - at Grand Slams (4), Masters 1000 tournaments (3), ATP 500 (1) and Davis Cup (once, in 2019).
Schwartzman has taken a set off Federer once in his four meetings (one Grand Slam, two Masters 1000, one ATP 250) against the 20-time Grand Slam champion. The pair haven't met since 2017 Shanghai.
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