The American, who was seeking a historic 24th grand slam title at the return of an event she has won seven times, was tearful as she had to withdraw from the match.

Williams had broken Sasnovich and led 3-1, appearing to be in full control of Tuesday's contest on Centre Court.

But she suffered an ankle injury in the fifth game after seeming to slip while playing a forehand.

With her movement clearly limited, Sasnovich broke back and Williams left the court for treatment as she took a medical timeout.

She re-emerged to huge applause and bravely tried to continue but was visibly in severe discomfort.

The 39-year-old soon had to call a halt to proceedings with the match level at 3-3, having let out a scream of pain as she tried in vain to reach the ball.