Italy’s Camila Giorgi upset four-time champion Caroline Wozniacki 6-4 6-2 on Wednesday to reach the quarter-finals of the Connecticut Open, a final US Open warm-up hardcourt event.

Giorgi dispatched the former world No.1 in 78 minutes to book a last-eight date with Spain’s Garbine Muguruza, who eliminated Chinese qualifier Peng Shuai 6-2 3-6 6-3 in another second-round match.

Giorgi, ranked 38th, also ousted Wozniacki in last year’s US Open but lost their only other meeting this year at Eastbourne.

Wozniacki, whose best grand slam showing was a 2009 US Open runner-up effort, won the title at New Haven from 2008-2011, but saw her record at the Yale University event dip to 24-3.

The 24-year-old Dane’s only prior losses since Wimbledon came in three-set battles with world No.1 Serena Williams in Montreal and Cincinnati.

“I knew I was going to get limited break chances and when I did get them, I didn’t convert,” Wozniacki said.

The defeat does allow Wozniacki a few extra days to prepare for the year’s final grand slam event which starts on Monday.