Petrova and Srebotnik played their first Grand Slam together at this year's Australian Open, falling to the Williams sisters in the third round, but they have now gone deep at every major since - they were semifinalists at the French Open, quarterfinalists at Wimbledon and now quarterfinalists here.
The other third round matches saw No.8 seeds Ashleigh Barty and Casey Dellacqua beat No.9 seeds Liezel Huber and Nuria Llagostera Vives, 64 63, and No.10 seeds Sania Mirza and Zheng Jie pull off a mild upset, cruising past No.6 seeds Anna-Lena Groenefeld and Kveta Peschke in straight sets, 62 63.
Both of those winners have already had breakthrough results this year - Barty and Dellacqua made the finals of the Australian Open and Wimbledon together, while Mirza and Zheng actually won the New Haven title together right before the Open - so it's no surprise they're having success in New York.
After not winning back-to-back matches at their two lead-up events, Errani and Vinci are now hoping to finish the summer hardcourt season on a high, something they did last year here - this was one of their three Grand Slam titles together (2012 French Open, 2012 US Open and 2013 Australian Open).
Vinci was very happy after their win on Sunday, as evidenced by her tweet below - how's your Italian?