Daria Gavrilova stunned second seed Maria Sharapova at the Miami Open on Thursday, while Caroline Wozniacki breezed into the third round.

Gavrilova, ranked 97th, was a 7-6 (7-4) 6-3 winner over Sharapova, who amassed 34 unforced errors as she bowed out at the first time of asking in Florida.

Wildcard Gavrilova, who represents Russia but is awaiting Australian citizenship, broke Sharapova four times from six chances.

Gavrilova made 28 unforced errors herself and produced only 10 winners, but one of the latter came on break point in the eighth game of the second set - as she nabbed the decisive break of serve.

A crunched backhand return winner saw Gavrilova break to love and move 5-3 up, and the 21-year-old held her nerve to beat world number two Sharapova in one hour, 49 minutes at the WTA Premier hard-court event.

Wozniacki (seeded fourth), Agnieszka Radwanska (seventh), Ekaterina Makarova (eighth), Andrea Petkovic (ninth) and Carla Suarez Navarro (12th) all enjoyed straight sets wins to advance to the last 32.

Former world number one Wozniacki thrashed Madison Brengle 6-0 6-1, 2012 champion Radwanska got past Anna Schmiedlova 6-4 7-5, left-hander Makarova was too good for Karin Knapp 6-1 6-3, Petkovic dismissed Christina McHale 6-2 6-2, and Suarez Navarro accounted for qualifier Stefanie Voegele 6-3 6-1.

Joining Sharapova among the seeds to exit Miami early were Barbora Zahlavova Strycova (19th), Caroline Garcia (25th) and Varvara Lepchenko (28th).

Kristina Mladenovic beat Zahlavova Strycova 7-5 6-2, Garcia blew two second-set points in a 6-3 7-6 (11-9) loss to Kurumi Nara, while Kaia Kanepi ousted Lepchenko 6-2 6-4.

Paula Badosa Gibert made the most of her fortune, the Spanish wildcard downing lucky loser Zheng Saisai 6-1 7-5.

Originally scheduled to play 18th seed Peng Shuai, Badosa Gibert saw her opponent withdraw due to a back injury - and she capitalised against the world number 75 Zheng.

Karolina Pliskova, the 14th seed, fought back to down Annika Beck 2-6 6-3 6-4, while 16th seed Venus Williams - a three-time champion in Miami but not since 2001 - defeated qualifier Urszula Radwanska 6-3 6-2.

Irina-Camelia Begu won a thriller over Tereza Smitkova, the 31st seed advancing 5-7 6-4 6-4, while 23rd seed Sam Stosur overcame a hiccup to down qualifier Pauline Parmentier 6-1 3-6 6-0.

Alize Cornet, the 22nd seed, cruised past Elena Vesnina 6-4 6-1, while 26th seed Elina Svitolina was too good for Bojana Jovanovski 6-3 7-6 (7-3).