For comparison, during a match last month, Andy Murray and Julien Benneteau had a rally that lasted 53 shots, and it was the longest either of them could remember playing in competition.

The rally between Nelson and Hepner occurred in the first round of the $50,000 Virginia Slims-sponsored Ginny tournament at the Raintree Swim and Racquet Club in Richmond, Va., with Nelson finally prevailing, 6-4, 7-6 (11).

The 6-hour-31-minute marathon was itself the longest match in tennis history for nearly 20 years and remains the longest match completed on a single day. (In the 2004 French Open, Fabrice Santoro defeated Arnaud Clément in 6:33. That match, however, was suspended by darkness in the fifth set, so the final 1:55 was played the next day.)

Both Nelson and Hepner seem vaguely embarrassed that their names are in the record books.

“Even now, just thinking about it, my stomach is starting to hurt,” Hepner said. “I had a lot going on in my personal life at that time and I was trying to turn my career around and it was getting tougher to do. But I didn’t stay out there for six hours to get attention; I just wanted to win that match badly.”

Image Vicki Nelson Dunbar played Martina Navratilova at Wimbledon in 1987. Credit... Photo Courtesty of Vicki Nelson Dunbar

Hepner, who was then 25, retired from the sport soon after and now lives in Redwood City, Calif. She is a teacher, property manager and competitive chess player, but only rarely plays tennis and no longer has any connections to the professional tennis world.