In a Wimbledon full of surprises and upsets, the biggest upset of all has happened in the round of 16.

Top seed Serena Williams, the heavy favorite, was stunned by 23 year old German Sabine Lisicki 6-2, 1-6, 6-4.

Lisicki was in deep trouble, having lost the second set 1-6 and down 0-3 in the third.  But the German battled back to tie the match at 4-4.  Williams made a critical unforced error in the ninth game, hitting an easy, open court shot long to give Lisicki the break she needed.

In the two sets she lost, Williams only hit 55% of her first serves.

Williams saved one match point and had the advantage in the tenth game, but Lisicki won three straight points, including one ace, to close out the match.  Lisicki dropped face down on the court after hitting a winner down the line.

The loss by Williams leaves #4 Agnieszka Radwanska as the highest seed left in the ladies draw..  Lisicki will face unseeded Kaia Kanepi of Estonia in the quarterfinals.  Kanepi disappointed the crowd by ousting Laura Robson of Great Britain, 7-6, 7-5.