Lexington, Aug 14 (IANS): Twenty three-time Grand Slam champion Serena Williams overcame a stern test from elder sister Venus to make it to the quarter-finals at the inaugural Top Seed Open.

Serena, No. 1 seed, defeated Venus 3-6, 6-3, 6-4 in a thrilling match that lasted for two hours and 19 minutes on Thursday played at the Centre Court.

"I've lost a few tight sets lately, so I was telling myself I really wanted to win this one and try to focus on those last two games," Serena said in her on-court interview as per the WTA website.

"I'm super relaxed. Having no crowd sort of makes things more relaxing. I've practised in louder places than this court!"

"I honestly didn't come here to win. For the first time in my career, I came here to win some matches and see what happens. I haven't had this much time off since the baby, so now I'm just trying to get some rhythm and see what happens," she added.

It was Serena's 19th win over the five-time Wimbledon champion in their 31 encounters.

Serena will next face Shelby Rogers -- who defeated rising Canadian star Leylah Annie Fernandez 6-2, 7-5 -- for a spot in the semi-finals.