In the World of Professional Tennis during the Modern Era only twice thus far have there been
four different men and four different women Slam Champions within a Calendar year.

1990

Australian Open
Ivan Lendl
Steffi Graf

French Open

Andres Gomes
Monica Seles

Wimbledon
Stefan Edberg
Martina Navratilova

US Open
Pete Sampras
Gabriel Sabatini

1998

Australian Open
Petr Korda
Martina Hinigs

French Open
Carlos Moya
Aranxta Vicario

Wimbledon
Pete Sampras
Jana Novotna

US Open
Patrick Rafter
Lyndsay Davenport