Belgian Justine Henin defeated world No. 2 Caroline Wozniacki 6-7 (5/7), 6-3, 6-4 to reach the semifinals on Wednesday at the Miami ATP and WTA tournament, her fourth event since returning from retirement.
Henin, a former world No. 1, could face compatriot Kim Clijsters or Australian Samantha Stosur, who play later on Wednesday in the semifinals.
Henin, currently ranked 33rd in the world and playing on wild card invitation, has already beaten four seeded players in a row.
She's 16-3 since ending a 20-month retirement in January, and she'll move back into the top 30 in next week's rankings.
Three-time champion Venus Williams will play 13th seed Marion Bartoli in the other women's semi-final on Thursday.
Henin, winner of seven Grand Slam titles, has never won in Miami. Her best finish here was in 2007, when she lost to Serena Williams in the final.
She was playing for the first time against the 19-year-old Wozniacki, who said she wasn't surprised Henin's comeback had gotten off to such a quick start.