Serena Williams wins at Stanford in final Olympic tuneup

Eight days after winning Wimbledon, Williams saved a set point and won the final four games of the opening set. It was the 43rd WTA Tour championship of Williams' career, tying older sister Venus for the most among active players.

The first All-American WTA final on home soil in eight years was hardly a one-sided affair.

The 20-year-old Vandeweghe, who failed to make it out of qualifying and only got into the main draw when Bojana Jovanovski withdrew with an injury, moved the 14-time Grand Slam champion and her highlighter-yellow shirt outfit all over the court to give Williams her only real challenge of the week.