Basel, Switzerland (SportsNetwork.com) - Reigning champion Juan Martin del Potro and five-time titlist Roger Federer were a pair of straight-set quarterfinal winners Friday at the $1.955 million Swiss Indoors Basel.

The top-seeded Argentine slugger del Potro recorded his 300th career ATP match win by handling oft-injured Frenchman Paul-Henri Mathieu 6-4, 6-4 at St. Jakobshalle.

"It's a pleasure winning my 300th match on tour, doing it here in Basel, against Mathieu," said del Potro. "I think I played really well. I don't know if I deserved that, but it's like a gift for all my efforts for many, many years of work. I am looking forward to [trying to] reach the final once again. I am trying to go far and repeat what I did last year."

Del Potro, who upset the Swiss hero Federer in last year's Basel finale, is seeking a trip into a third final in three events, having recently titled in Tokyo and finished as a runner-up at the Shanghai Masters.

The Argentine's semifinal opponent on Saturday will be another Frenchman, Edouard Roger-Vasselin, who outlasted German Daniel Brands 6-3, 4-6, 6-3 on Day 5.

The third-seeded former world No. 1 great Federer, meanwhile, topped eighth- seeded Bulgarian Grigor Dimitrov 6-3, 7-6 (7-2). The rising Dimitrov, nicknamed "Baby Fed," was fresh off his first-ever ATP title in Stockholm last week.

The 32-year-old Federer, who is a nine-time finalist at his hometown Basel event, will face rising Canadian Vasek Pospisil on Saturday. Pospisil got past Croat Ivan Dodig 7-6 (13-11), 6-4.

The 2013 Basel titlist will earn $475,000.