Radwanska had never before made it past the quarterfinals in New Haven, but had a relatively easy trip this year that included straight set wins over Jelena Ostapenko of Latvia, Kirsten Flipkens of Belgium and a 6-1, 6-1 semifinal victory over two-time champion Petra Kvitova.
The Polish star didn't drop a set during the tournament, her 19th WTA championship. She took control of the final from the start, winning 20 of the first 27 points, jumping out to a 5-0 lead.
She becomes the first top seed to win since Caroline Wozniacki did it in 2011. The title is Radwanska's second this season after taking the Shenzhen Open in China in January.
She takes home USD 130,300 for winning in Connecticut. The tournament's prize money was USD 695,900. (PAP)
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