Simon, the No. 6 seed, stopped second-seeded Juan Martin del Potro 6-4, 6-3. Simon saved all three break points he faced.
The first break of the match came in the 10th game of the first set and Simon took the lead in the second set with a fourth-game break.
Top-seeded Tomas Berdych got past No. 7-seeded Jerzy Janowicz 6-3, 6-7 (0-7), 6-3. He didn't see a break point and, even with shutout in the tiebreaker, won nearly three-quarters of the points on serve.
Berdych cashed in two of his three break chances.
Jo-Wilfried Tsonga, the third seed, survived an extended third-set tiebreaker for a 4-6, 6-3, 7-6 (12-10) quarterfinal win over Bernard Tomic. Tsonga had 19 aces and dropped just 22 points -- half of those in the third set -- in 16 games serving.
Tursunov takes on Berdych in the semifinals Saturday. Berdych had won five of their previous six meetings. Tsonga is 4-3 versus Simon, but only one of the matches -- a Simon win -- has been since 2010.
Swim Week Miami Beach 2014 [PHOTOS]