Roger Federer and Stan Warwinka impress in reaching US Open semi-finals

Roger Federer saved precious time and valuable energy as he strolled into the US Open semi-finals with a ruthless win over France’s Richard Gasquet.

With rain forecasted for Wednesday night and most of Thursday at Flushing Meadows, there was a looming possibility the men’s quarter-finals could be delayed, therefore encroaching on the players’ recovery time ahead of the semi-finals on Friday.