Unseeded Romanian Sorana Cirstea earned the biggest win of her career with a 6-4, 6-4 victory over Australian Open champion and world No.2 Aryna Sabalenka on Wednesday to reach the Miami Open semi-final.

Cirstea, who has yet to drop a set in Miami and is the last unseeded player in the draw, delivered a stunning performance while taking advantage of some untimely double faults to become only the third person to beat Sabalenka this year.

With the win, the 32-year-old Cirstea reached her second WTA 1000 semi-final nearly 10 years after reaching her first.

“I am a bit speechless,” said world No. 74 Cirstea.“I came out knowing that it was going to be a really tough match.

“Aryna hits so hard, so I knew I had to hold my ground and I am very, very happy with my performance today and it’s a bit unexpected to be honest.”

Cirstea broke to open the match but Sabalenka dropped just three points across her next three service games before breaking the Romanian to draw level at 4-4.

But Cirstea held firm against Sabalenka’s power and broke right back before sealing the first set in emphatic fashion with an ace.

The Romanian broke to start the second set when Sabalenka double-faulted at 30-40 and then held to love for a 2-0 lead but the Belarusian briefly turned up the heat and looked to have found her way before letting it slip.

Sabalenka squandered a break point chance while leading 3-2 and then double-faulted while facing a break point in the next game as Cirstea went ahead 4-3 and never looked back.

Sinner sails

On the men’s side, a two-hour mid-match rain delay could not cool off sizzling Jannik Sinner, who crushed unseeded Finn Emil Ruusuvuori 6-3, 6-1 in their one-sided quarter final. The 10th-seeded Italian ripped a backhand return winner to capture the first set and rolled from there to improve to a career 5-0 against Ruusuvuori.

Rain washed out Wednesday’s remaining matches.

Andreescu injury

Canada’s Bianca Andreescu suffered two torn ligaments in her left ankle this week and is unsure when she will be fit to return to action, the former US Open champion said on Wednesday.

Andreescu retired from her fourth-round match against Russia’s Ekaterina Alexandrova on Monday and left the court in a wheelchair.

“It’s tough to say exactly how long it will take, but let’s just say it could’ve been much worse !!” Andreescu wrote on Twitter.