Federer crashes out of US Open

Roger Federer has been knocked out of the US Open after losing his quarterfinal match against Bulgaria's Grigor Dimitrov in five sets.

Dimitrov will now play Daniil Medvedev in the semi-finals after the Russian battled through injury to get the better of Stan Wawrinka.

Meanwhile, Serena Williams has also stormed into the semi-finals of the US Open.

She beat China's Wang Qiang in just 44 minutes to keep her hopes of winning a record-equalling 24th Grand Slam title alive.

The American will face Ukraine's Elina Svitolina in the final four after she beat Johanna Konta.