Petrova, who reached the quarterfinals at Wimbledon this year, clinched the win with a forehand return on her second match point to win her first championship since the 2007 Tier II Paris indoor tournament and her first outdoors since the Tier I Berlin Open on clay in May 2006.
Petrova, the third consecutive Russian to win the Tier III tournament, earned $28,000. France's Dechy, making her first finals appearance since the 2004 New Haven event, earned $15,000.
The players traded service breaks through the first three games before Petrova held for 3-1 lead. Playing more aggressively, the Russian had 17 winners to Dechy's four while committing nine unforced errors to five for Dechy in the first set.
The second set was tied 1-1 when Dechy double-faulted on game point, and Petrova went on to win the last five games of the match.
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