NEW YORK (WFAN/AP) – Tennis fans at the US Open witnessed a pretty big upset Friday.

WFAN Extra: US Open Guide

READ MORE: FBI Says Body Found In Grand Teton National Park Believed To Be Gabby Petito

Maria Sharapova, the 2006 US Open champion, was upset in the third round by Flavia Pennetta.

Sharapova lost 6-3, 3-6, 6-4 to the 26th-seeded Italian on Friday. Sharapova had been 12-0 in three-set matches this year, including her first-round win.

READ MORE: NYC Restaurant Owners Sound Off On Vaccine Mandate

Pennetta broke serve to clinch the victory in a match full of breaks, with the third-seeded Russian struggling with her serve.

Sharapova had reached her first Grand Slam final since 2008 shoulder surgery when she was the runner-up at Wimbledon.

MORE NEWS: 2021 Primetime Emmy Awards: Complete List Of Winners And Nominees

Pennetta will next face 13th-seeded Peng Shuai of China, who beat 19th-seeded Julia Goerges 6-4, 7-6 (1).