I'm certain I can't think of them all but here's a few that come to mind in no particular order or era.
Steffi Graf vs Monica Seles
Steffi Graf vs Gabriel Sabatini
Steffi Graf vs Arantxa Sanchez Vicario
Steffi Graf vs Martina Navratilova
Martina Navratilova vs Chris Evert
Chris Evert vs Tracy Austin
Lyndsay Davenport vs Martina Hingis
Martina Hingis vs Anna Kournikova
Lyndsay Davenport vs Venus Williams
Venus Williams vs Serena Williams
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John McEnroe vs Borne Borg
John McEnroe vs Jimmy Connors
Ivan Lendl vs John McEnroe
Ivan Lendl vs Boris Becker
Ivan Lendl vs Stefan Edberg
Ivan Lendl vs Mats Wilander
Boris Becker vs Stefan Edberg
Pete Sampras vs Andre Agassi
Andre Agassi vs Jim Courier
Roger Federer vs Rafael Nadal
Like I said, there are undoubtedly great rivalries on either side that I've forgotten so consider this a start. Help me out if you can think of more.
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