Errani captured the French Open tuneup with a 7-5, 6-4 triumph on the clay court.
Errani converted six of her seven break point chances in the match but still needed 1 hour, 43 minutes to close Vesnina out.
Errani has been on a roll, winning all three of her finals appearances this year. Vesnina played in her first final of the year and is 0-6 lifetime in title matches.
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