Sam Stosur and Serena Williams played one of the first matches on a packed round of 16 Monday.
Breakout star Garbine Muguruza Blanco was also in action, but lost to Agnieszka Radwanska, 63 62.
Serena Williams fired 20 aces against Sam Stosur to win, 75 63, revenge for the US Open final.
Caroline Wozniacki fired an ace on set point then cruised for a 76(6) 60 win over Yanina Wickmayer.
In one of the last fourth round matches, Dominika Cibulkova led Victoria Azarenka by 61 40...
Victoria Azarenka overcame Dominika Cibulkova, 16 76(7) 75, extending her perfect season to 26-0.
In the last fourth round match, Ana Ivanovic fell to Venus Williams under the lights, 67(4) 62 62.
Maria Sharapova was the first player to move into the semifinals Tuesday, beating Li Na, 63 60.
At night, Caroline Wozniacki was a wall in a 64 64 win over five-time Miami champ Serena Williams.
Venus Williams hadn't played since the US Open, but won four matches to get to the quarterfinals.
Agnieszka Radwanska was too solid, winning a tight first set then rolling over Venus Williams, 64 61.
Venus Williams waved to the crowd after the loss. She is a three-time Sony Ericsson Open champion.
Marion Bartoli became the last player into the final four, pulling off a Wednesday night stunner.
Marion Bartoli ended Victoria Azarenka's perfect start to the season with a 63 63 upset victory.
Marion Bartoli now has three wins over World No.1s, also beating Justine Henin and Jelena Jankovic.
Sara Errani and Roberta Vinci answered fan questions on their day off between doubles matches.
In Thursday's first semifinal, Caroline Wozniacki came from 4-1 down to win the first set, 6-4.
Maria Sharapova was too tough, getting right back to work and beating Caroline Wozniacki, 46 62 64.
Marion Bartoli served the ball to Agnieszka Radwanska in the second semifinal Thursday night...
Agnieszka Radwanska broke Marion Bartoli in all nine of her service games to score a 64 62 win.