US Open: Big Guns Complete Final Four Line-up

The final four were decided in the US Open as the big guns made it business as usual.(All AFP Photos)

Roger Federer kept himself on track for his 18th Grand Slam as he beat Kevin Anderson to seal a semifinal berth.

Stanislas Wawrinka set up a semifinal battle with fellow Swiss Roger Federer.

Flavia Pennetta will take on Simona Halep in the semis for a chance to play her first US Open final.