Ana Ivanovic, looking for her first win over Kim Clijsters, built a 5-1 third set advantage.
Kim Clijsters saved five match points to edge Ana Ivanovic in the round of 16, 76(4) 36 76(5).
In the first quarterfinal, Andrea Petkovic rallied from 2-4 in the third set to win, 26 62 64.
After her win over Jelena Jankovic, Andrea Petkovic did her trademark Petko Dance on Stadium.
Maria Sharapova battled for three hours and 29 minutes to beat Alexandra Dulgheru on Tuesday.
On her way to the doubles final, Daniela Hantuchova signed autographs for her many, many fans.
Agnieszka Radwanska served to Vera Zvonareva but fell to the Russian in the quarters, 75 63.
Vera Zvonareva reached her second Sony Ericsson Open semifinal, also doing it back in 2008.
In the last quarterfinal match, Victoria Azarenka defeated Kim Clijsters routinely, 63 63.
During her deep doubles run, Sloane Stephens stopped and signed autographs along the way.
Vera Zvonareva took some time out in Week 2 to speak to renowned tennis writer Bud Collins.
Maria Sharapova rebounded to beat Andrea Petkovic in a hard-hitting semifinal duel, 36 60 62.
Although she fell in the semifinals, Andrea Petkovic's run will propel her into the Top 20.
Maria Sharapova reached her third Miami final, having been a runner-up here in 2005 and 2006.
Victoria Azarenka, a champion here in 2009, beat Vera Zvonareva in the second semifinal, 60 63.