Venus Williams cried on court, Lindsay Davenport wept in the showers while Monica Seles just shook her head, struggling to explain the manner in which her form deserted her on an emotional afternoon at the All England club.

The women's quarter-finals produced some superlative tennis, notably in the clash between defending champion Martina Hingis and the French Open title holder Arantxa Sanchez Vicario which spawned three combative sets. There was also much to admire in the manner in which Jana Novotna subdued Venus Williams, a contest where speed of thought rather than limb proved decisive.

Then there was Natasha Zvereva, conqueror of Steffi Graf, who completed a notable double with victory over Seles. The 27year-old unseeded player from Belarus, whose ambition on quitting tennis is to become the best farmer in the province of Minsk, will face Frenchwoman Natalie Tauziat in the semi-finals today after the later's 6-3, 6-3 win over number two seed Davenport.

But it was the opening match on Centre Court which captivated an appreciative crowd, Hingis displaying a maturity and intelligence that belied her tender years in edging past a wonderfully obdurate challenge from Sanchez Vicario.

As is her wont at these championships, the Spaniard conceded the opening set for the fourth time in five matches, but as in previous rounds her rehabilitation was swift and ruthless. The essence of Sanchez Vicario's game is her ability to chase down the irretrievable and patiently construct openings, content to bide her time and rarely given to the impetuous swipe.

Rarely offering cheap points, she therefore exposes any flaws in the technique or temperament of her opponents, frustrating or goading them into the injudicious option. Having dropped the first set 6-3, trailing 3-2 and 0-40 on her serve, Sanchez Vicario produced inspirational tennis.

She staved off three break points to win the game, broke in the next and then, for good measure, took the following two games and the set 6-3. Cleverly using the pace of Hingis's groundstrokes, the Spaniard began to dictate the course of rallies, sending her opponent scuttling around the court.

Hingis continued to create opportunities on the Sanchez serve but could not convert as the Spaniard saved three break points at 12 in the third set and indeed enjoyed a remarkable sequence of escapes, managing to defy the world number one on 11 occasions in succession over a series of four service games.

To her credit the 17-year-old Swiss girl realised that a change in approach was required and she began to vary both the length and pace of her ground strokes. On her 12th break point, in the sixth game of the final set, Hingis finally managed to close out the game, earning a 4-2 lead.

Her opponent's fighting spirit is legendary on the women's tour and few would have been surprised by Sanchez's swift rejoinder, breaking Hingis to love. Finding herself in familiar territory at 0-40 in the next game, the French Open champion clawed back two points before hitting a forehand long: it was to prove a decisive error as Hingis held serve to clinch the set and the match.

A relieved defending champion admitted: "I think it was a very good match. I mean there were some long rallies, very well played from both sides, not too many mistakes." She will now face Jana Novotna in today's other semi-final, a repeat of last year's final. The Czech survived a tough examination from a tenacious Venus Williams.

The American teenager was the victim of two questionable calls which caused her normally stoic expression to alter considerably. On the first occasion she berated a line judge while, the second time, displayed a vulnerability that bespoke her years, when shedding a couple of tears at a changeover having been the recipient of another game altering decision.

To her credit, while tears may have been inappropriate, she displayed great heart in forcing the second set tie-break but then produced her worst tennis of the match to lose the tie-break 7-2 and the contest 7-5, 7-6.

It was the Seles defeat which perhaps caused the biggest upset but, for those who saw the action, the former world number one could rarely be credited with competency, let alone the requisite level of tennis that is expected of her. "I couldn't string two points together and I am at a loss to explain why."