Australian-based Daria Gavrilova produced the biggest upset of the Miami Open when she ousted world No.2 Maria Sharapova.

The 21-year-old Gavrilova shocked Sharapova 7-6 (7-4) 6-3 in one hour and 49 minutes in their second round clash on Thursday.

It’s a result to warm hearts Down Under as Gavrilova, the girlfriend of Australian young gun Luke Saville, is seeking Australian citizenship and already represents Australia at grand slam events.

Having only broken into the world top 100 on Monday and never beaten anyone ranked higher than 39th, world No.97 Gavrilova was as surprised as Sharapova by her victory as she joined Samantha Stosur – a 6-1 3-6 6-0 winner over Frenchwoman Pauline Parmentier – in the third round.

“I still can’t realise that it’s my dream,” said Gavrilova, who said she had dreamed of beating Sharapova ever since she saw her fellow Russian beat Serena Williams in the Wimbledon final in 2004.

The loss was the worst defeat five-time Grand Slam winner Sharapova has endured in Miami since she lost in the first round on her debut in 2003.

“It’s sport, and I happened to lose the match,” Sharapova said. “Of course it’s a bit of a surprise … I’m expected to win.

“But that’s one of the reasons why we play the matches – you still have to go out and win it no matter if you’re the favorite. Today I didn’t.”

Remaining women’s seeds fared better, with six of the top 16 making it through to the third round.

Number four Caroline Wozniacki lost just one game in a 6-0 6-1 hammering of Madison Brengle, while Polish seventh seed Agnieszka Radwanska defeated Anna Schmiedlova 6-4 7-5.

Eighth-seeded Russian Ekaterina Makarova, German ninth seed Andrea Petkovic, 12th-seeded Spaniard Carla Suarez Navarro, number 15 Karolina Pliskova of Czech Republic and 16th-seeded Venus Williams all advanced.

Williams, playing her first match since February 27, defeated Radwanska’s younger sister Urszula 6-3 6-2 to set up a meeting with Stosur.