Daria Kasatkina produced a sensational performance against Venus Williams ©Getty Images

Naomi Osaka and Daria Kasatkina each produced shock upsets to stun Simona Halep and Venus Williams in the Indian Wells Masters semi-finals in California.

Japan's Osaka, ranked a lowly 44th in the world, thrashed Romania's below par world number one Halep 6-3, 6-4 in just 64 minutes.

Russia's Kasatkina then recovered from a set down to beat world number eight Williams 4-6, 6-4, 7-5.

The two winners, who are both aged 20, will now meet in the final tomorrow at the Indian Wells Tennis Garden.

The result continued an especially remarkable tournament for Kasatkina, who has also knocked out US Open champion Sloane Stephens, Australian Open winner and world number two Caroline Wozniacki and Germany's world number 10 Angelique Kerber.

"[After a] match like this, you're just speechless," she said. 

"Too many emotions and you cannot explain everything. 

"It's one of the best nights in my life, for sure."

Naomi Osaka also produced a shock upset ©Getty Images
Naomi Osaka also produced a shock upset ©Getty Images

Osaka had also beaten Russia's Maria Sharapova, Poland's Agnieszka Radwanska and Czech Republic's Karolina Plíšková on her way to the final.

Canada's Milos Raonic returned to form to reach the men's semi-finals.

The 32nd seed overcame 18th seeded home player Sam Querrey 7-5, 2-6, 6-3.

He will now face Argentina's sixth seed Juan Martin Del Potro for a place in the final.

Del Potro won 3-6, 6-3, 6-4 against Germany's Philipp Kohlschreiber.

Swiss top seed Roger Federer will face Croatia's Borna Ćorić in the other semi-final.