The US Open women's draw was blown wide open by a series of upsets on Friday but it was business as usual on the men's side with Roger Federer leading a parade of seeds into the third round at the year's final Grand Slam.

The shockwaves began early on another sunny day at Flushing Meadows with 32-year-old qualifier Mirjana Lucic-Baroni dismissing Romanian second seed Simona Halep 7-6 (8-6,) 6-2 to reach the fourth round.

The tremors continued as Swiss teen Belinda Bencic ousted sixth-seeded German Angelique Kerber 6-1, 7-5 to reach the round of 16 in her US Open debut.

The tournament also lost a fan favourite when Italy's Sara Errani posted her first career win over twice champion and 19th seed Venus Williams, coming out on top in an absorbing roller-coaster clash 6-0, 0-6, 7-6 (7-5).

By the time fifth seed Maria Sharapova had closed out the action under the Arthur Ashe Stadium floodlights with a laboured 6-2, 6-4 win over Germany's Sabine Lisicki the top of the women's draw had lost four of the top eight seeds.

The top 10 men's seeds, however, remain intact.

Federer, Spanish fourth seed David Ferrer, sixth-seeded Czech Tomas Berdych and seventh-seeded Bulgarian Grigor Dimitrov all advanced on Friday. The highest-ranked casualty was Ernests Gulbis of Latvia, the 11th seed, who was ousted by 45th-ranked Dominic Thiem of Austria 4-6, 3-6, 6-4, 6-3, 6-3.

Federer, chasing an 18th Grand Slam Title, served up a tidy 6-4, 6-4, 6-4 win over big-hitting Australian Sam Groth to ease into the third round.

Ferrer reached the third round without lifting his racket when Australian Bernard Tomic withdrew with a hip injury, while Dimitrov breezed into the third round with a 6-1, 6-2, 6-2 win over Israel's Dudi Sela.

Berdych had a much tougher time, needing five sets and three hours 45 minutes to tame Martin Klizan of Slovakia 6-3, 4-6, 6-2, 3-6, 6-3.

Richard Gasquet, seeded 12th, and Gael Monfils, 20th, advanced in straight sets to set up an all-French collision for a berth in the fourth round.

Paes-Stepanek advance

Leander Paes and Czech partner Radek Stepanek entered the men’s doubles prequarterfinals with a straight-set victory in the second round,The sixth seeded pairing defeated Chinese Taipei’s Yen Hsun-Lu and Czech Republic’s Jiri Vesley 7-6 (7-3), 6-3 in a contest which lasted an hour and 23 minutes.

Results (prefix denotes seedings): Men’s singles, second round: Dominic Thiem (Aut) bt 11-Ernests Gulbis (Lat) 4-6, 3-6, 6-4, 6-3, 6-3; 17-Roberto Bautista (Esp) bt Tim Smyczek (US) 6-3, 6-2, 6-1; 26-Gilles Simon (Fra) bt Federico Delbonis (Arg) 6-4, 3-6, 7-6 (7-0), 6-1; 12-Richard Gasquet (Fra) bt Paolo Lorenzi (Ita) 7-6 (7-4), 6-3, 6-3; 7-Grigor Dimitrov (Bul) bt Dudi Sela (Isr) 6-1, 6-2, 6-2; 14-Marin Cilic (Cro) bt Illya Marchenko (Ukr) 7-6 (7-2), 6-2, 6-4; 20-Gael Monfils (Fra) bt Alejandro Gonzalez (Col) 7-5, 6-3, 6-2; 6-Tomas Berdych (Cze) bt Martin Klizan (Svk) 6-3, 4-6, 6-2, 3-6, 6-3; Adrian Mannarino (Fra) bt 15-Fabio Fognini (Ita) 6-3, 6-4, 6-1.

Women’s singles(third round): 5-Maria Sharapova (Rus) bt 26-Sabine Lisicki (Ger) 6-2, 6-4; 14-Lucie Safarova (Cze) bt 22-Alize Cornet (Fra) 6-3, 6-7 (3-7), 6-4; Belinda Bencic (Sui) bt 6-Angelique Kerber (Ger) 6-1, 7-5; 13-Sara Errani (Ita) bt 19-Venus Williams (US) 6-0, 0-6, 7-6 (7-5); Mirjana Lucic-Baroni (Cro) bt 2-Simona Halep (Rou) 7-6 (8-6), 6-2; 9-Jelena Jankovic (Srb) bt Johanna Larsson (Swe) 6-1, 6-0; 10-Caroline Wozniacki (Den) bt 18-Andrea Petkovic (Ger) 6-3, 6-2.