Image:Fourth seed David Ferrer was first up on Louis Armstrong against 26th seed Gilles Simon
Image:Simon, the former world No 6, pulled off a shock third-round win, prevailing 6-3 3-6 6-1 6-3 to send Ferrer packing
Image:Marin Cilic will play Simon in the fourth round after the 14th-seeded Croat hit 13 aces during a four-set win over South African Kevin Anderson
Image:Mirjana Lucic-Baroni was playing in the fourth round of a grand slam for the first time since Wimbledon in 1999
Image:But Lucic-Baroni's run came to an end, 11th seed Sara Errani seeing her off 6-3 2-6 6-0 in an hour and 46 minutes
Image:It was hot work for 2006 champion Maria Sharapova in her fourth-round match against Caroline Wozniacki, still searching for her first major title
Image:Wozniacki, who reached the final five years ago, emerged victorious, 6-4 2-6 6-2 in two hours and 37 minutes
Image:Wozniacki will play Errani in the quarter-finals
Image:Roger Federer was a break down to Marcel Granollers in the first set when play was suspended due to a thunderstorm
Image:Heavy rain soon arrived at Flushing Meadows
Image:Conditions eased later in the day and groundstaff quickly got the courts ready for a resumption
Image:Granollers won the opening set 6-4 when play resumed
Image:But Federer - a five-time champion in New York - stepped up a gear for the remainder of the match to earn a 4-6 6-1 6-1 6-1 victory
Image:Sixth seed Tomas Berdych eased past Teymuraz Gabashvili in straight sets
Image:At 17, Belinda Bencic beat ninth seed Jelena Jankovic to become the youngest US Open quarter-finalist since 1997
Image:Seventh seed Grigor Dimitrov lost the first set 6-0 to David Goffin before turning it around to claim a four-set success
Image:Next up for Dimitrov in the fourth round is Gael Monfils, who saw off fellow Frenchman Richard Gasquet in straight sets
