Vinci upset the top-seeded Errani 6-3, 3-6, 6-3 in the Palermo final, marking a rare triumph over her doubles partner in the first all-Italian championship match at the clay-court event since 2009.
The 30-year-old used seven aces to improve to 9-1 in career singles finals while notching her second 2013 title in the 2-hour, 11-minute affair.
Errani, meanwhile, committed six double faults in the loss.
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