Top seed Tomas Berdych and former champion Jo-Wilfried Tsonga were a pair of hard-fought quarterfinal winners, while defending champ Juan Martin del Potro went by way of the upset Friday at the $700,000 Open 13 tennis event.
The former Wimbledon runner-up Berdych snuck past seventh-seeded rising Pole Jerzy Janowicz 6-3, 6-7 (0-7), 6-3 in 1 hour, 54 minutes on the indoor surface at Palais des Sports.
The big-hitting match featured 27 aces, including 17 from the 6-foot-8 loser, who was unable to break his Czech counterpart on Day 5. Berdych managed a pair of key breaks en route to victory.
Berdych's semifinal opponent on Saturday will be Russian qualifier Dmitry Tursunov.
The second-seeded del Potro was knocked out by sixth-seeded Frenchman Gilles Simon in straight sets, 6-4, 6-3, in 81 minutes. Simon notched a pair of breaks, while del Potro was unable to break his French opponent on Friday.
The towering Argentine del Potro, who beat French favorite Michael Llodra in last year's Marseille finale and in a second-rounder here on Thursday, was fresh off his indoor title in Rotterdam last week.
The capable former top-10 star Simon captured the Open 13 tournament back in 2007.
Meanwhile, the third-seeded French star Tsonga fought back to secure his semifinal berth, as the former Australian Open runner-up outlasted Aussie Bernard Tomic 4-6, 6-3, 7-6 (12-10) in 2 hours, 5 minutes. Tsonga, who captured this event in 2009, pumped out 19 aces in the win.
Tsonga and Simon will battle in an all-French affair on Saturday.
The aforementioned Tursunov held off Luxembourg's Gilles Muller 7-6 (9-7), 1-6, 7-5 to reach the final four.
The 2013 Marseille champion will earn $125,000.