World number four Williams controlled the match from the outset before eventually running out a 6-0 6-0 double-bagel victor.
Despite the apparent ease of her success, 30-year-old Williams has insisted that she took nothing for granted.
"She was fighting really hard," Williams told reporters. "You give people any type of chance, especially in tennis, the match is never over until you shake hands.
"There is always a comeback available. So I didn't want to give her that opportunity — or anyone that opportunity — to try to come back, especially her in particular.
"She was getting so pumped up and she never gave up. I thought that was really incredibly positive."
Williams is competing for her fourth title at Flushing Meadows.