US Open 2017: Juan Martin del Potro upsets Roger Federer to make into semis

Argentina's Potro stunned Federer in four sets to reach the US Open semi-finals at Flushing Meadows

Juan Martin del Potro of Argentina upset Roger Federer 7-5, 3-6, 7-6(8), 6-4 in the US Open tennis quarterfinals, denying tennis fans the chance at seeing the Swiss star play rival Rafael Nadal in the next round.

Since the draw was announced, fans have eagerly anticipated a semifinal matchup between Federer and Nadal. Despite their long rivalry, the two have never played against each other at Flushing Meadows, reports Xinhua news agency.

Federer and Nadal were the heavy favourites coming into the US Open after Andy Murray pulled out two days before the tournament began and Novak Djokovic and Stan Wawrinka skipped due to injuries. Federer is a five-time champion in New York, winning the title five consecutive times from 2004-08.

"I'm not more frustrating, to be honest. it's been a tough tournament throughout. I had struggled too much throughout the tournament to think too far ahead. In some ways I'm actually happy I made the quarters, so I'm not disappointed because it's been a good run this year already. Unfortunately, I ran into a guy who was better than me today," said Federer after the match on Wednesday.

In the other men's semi-final, Kevin Anderson of South Africa will play Pablo Carreno Busta of Spain.