Serena Williams has defeated Coco Vandeweghe to retain her Bank of the West Classic title at Stanford, Connecticut.
Despite being broken twice in the opening set, the recently-crowned Wimbledon champion came back to take it 7-5.
The second was more straightforward for the 30-year-old as she broke her fellow American once to win 6-3.
The triumph is Williams's fourth of the year following her victories in Charleston, Madrid and London.
