The 28-year-old from China dropped just three games in a 6-2, 6-1 win in New York City.

Swiss Bencic - at 17 the youngest player in the world's top 100 - had dispatched German Angelique Kerber and former world number one Jelena Jankovic of Serbia on her way to the quarter-finals.

With compatriot Li Na not making the journey to New York, Peng entered the final Grand Slam of the year as the highest ranked player from China.

Peng had never passed the fourth round of a Grand Slam.

Her previous best showing at the US Open was in 2011, when she lost to Italy's Flavia Pennetta in the fourth round.

"It's a little too exciting," said an emotional Peng afterwards.

She will face Dane Caroline Wozniacki in the last four.

The 2009 US Open finalist crushed Italian Sara Errani 6-0, 6-1.

The other two women's singles quarter-finals will be played tomorrow.

Marin Cilic will play Tomas Berdych for a place in the last four ©AFP/Getty Images



In the men's draw, 14th seed Marin Cilic beat 26th seed Gilles Simon of France in five sets to reach the last eight, winning 5-7, 7-6(3), 6-4, 3-6, 6-3.

His next opponent will be Czech sixth seed Tomas Berdych, who thumped 21-year-old Australian Dominic Thiem 6-1, 6-2, 6-3.

Frenchman Gael Monfils also won in straight sets, albeit needing to sweat a little more before dispatching Bulgarian Grigor Dimitrov 7-5, 7-6(6), 7-5.

Monfils will face Roger Federer in the quarters, after the Swiss second seed beat Spain's Roberto Bautista Agut 6-4, 6-3, 6-2.

Tomorrow will see United States top seed Serena Williams in quarter-final action against Pennetta, while Great Britain's Andy Murray will play a repeat of the 2012 US Open final for a place in the last four against top seed Novak Djokovic.