Serena Williams will face Naomi Osaka in the Australian Open semi-finals.

Rafael Nadal saw his bid for a 21st Grand Slam title end as Greek fifth seed Stefanos Tsitsipas fought back from two sets down to reach the Australian Open semi-finals.

The Spanish second seed, 34, was stunned as Tsitsipas claimed a 3-6 2-6 7-6 (7-4) 6-4 7-5 victory in Melbourne.

Tsitsipas, 22, broke out into a huge smile, almost in disbelief, after converting his third match point.

Tsitsipas will face Russia’s Daniil Medvedev in Friday’s semi-final.

Fourth seed Medvedev beat compatriot Andrey Rublev to reach the last four at the Australian Open for the first time.

The 25-year-old won 7-5 6-3 6-2 as his childhood friend Rublev, who was seeded seventh, struggled in the 29C temperatures at Melbourne Park.

ATP Finals champion Medvedev now puts a 19-match unbeaten streak on the line against Tsitsipas, who needed over four hours to overcome Nadal.

Meanwhile,  Serena Williams will continue her quest for a record-equalling 24th Grand Slam trophy against title favourite Naomi Osaka in the Australian Open semi-finals.

Williams, has rediscovered her best form at Melbourne Park but faces a tough test against Osaka whom she has not played since the Japanese beat her in a dramatic 2018 US Open final.

Third seed Osaka, has won a further two Grand Slam titles since that meeting – including the Australian Open in 2019.

Williams, the 10th seed, has shown great form in Melbourne as she aims to equal Margaret Court’s 24 major singles titles and reached the semi-finals by seeing off second seed Simona Halep in straight sets.

Both players have only dropped one set so far this tournament.