Steffi Graf - Always perfectly balanced, faultless footwork, able to measure a required speed better than anybody ever has. Never seemed stretched. Seemed to float in the air, such was her rate of bouncy small steps. Could have done ballet. Could have been a gold-winning sprinter, or long distance runner. Ran the Olympic qualifying time. The best all-round mover there's ever been, I think.
(2.39 - just watch this!)
(1.15 - amazing footwork!)
Martina Navratilova - Sliced and diced her way forward with lightning fast reflexes lent from, along with Serena, the strongest legs there have ever been in women's tennis. Nobody else in their mid-late 30s has been as close to their peak level as she was, by virtue of her physical strength.
(1.33 - Navratilova's last major win over Graf, at 35!)
(arguably her greatest ever performance)
Serena Williams - At sprint speed, the fastest woman there's ever been in 2002. The strength of her legs enables her to hit many shots off balance, although she needs it because her balance itself is sometimes poor.
(1.38; 5.08...classic movement, classic match...just breathtaking speed and strength from Serena)
Venus Williams - Another contender for the fastest woman ever in some areas. Her speed laterally across the baseline at her peak is possibly the greatest.
(6.16 - again, tremendous!)
Arantxa Sanchez-Vicario - Wrote the book on getting back into a point with speed and agility which seemed to know no bounds. Perfect balance and powerful sprint speed both forward and laterally. Had the same qualities as Nadal. Retrieved balls no player now or since would have ran for, and often won the point by inducing panic in her opponents through her ability to keep returning what would have been winning shots against anybody else.
(1.30 - typical Arantxa!)
(1.01..just impassable - watch Graf's face in the replay!)
(you might as well watch it all...oh the days when women's tennis had drama! Just brilliant!)
Jana Novotna - Cat-like movement, light footed, graceful mover. Lunged more than any player I remember other than Martina N. Leapt in the air several feet off the ground for her smashes, a sight which will go down in history. Incredibly fast reflexes, ever nimble.
Jennifer Capriati - A powerful mover, her speed lay in the strength of her legs. Excellent at covering out wide in particular.
Gabriela Sabatini - Light footed, graceful, yet a powerful athlete, with immense strength in her legs. Covered the net and the baseline with ease. With Navratilova declining, she was the only one who could truly compete with Graf in terms of athleticism from the baseline.
(this whole clip showcases her athleticism)
We don't need clips...
Jelena Jankovic - Light footed and fast reflexes. Has some of the qualities of Sanchez-Vicario.
Elena Dementieva - I know nothing of genetics, but if there is a 'Graf gene', then Dementieva has the closest make-up of all today's players. Not quite as well-drilled a mover, but the potential was there. No flaws in her movement.
Justine Henin - Perfect balance and footwork, positioning, as well as a sprint speed which was possibly the best in women's tennis during her era, relative to her height.
Honourable mentions to Kuznetsova, Date and Mauresmo and Coetzer.