Serena Williams preparing for doubles with sister, Venus, after advancing to third round of US Open

Serena Williams is still riding high after advancing to the third round of the US Open on Wednesday as she gets ready to play doubles with her sister, Venus.

It has been the biggest storyline of the US Open since she announced three weeks ago this may be her last time in Flushing — get Serena Williams as deep into the tournament as possible, hopefully all the way to the Final.

The six-time US Open champion has done her part so far, even treating fans to some doubles action Thursday night with her big sister.

Round 2 took a little more work than round 1 — one more set, to be exact, and Williams had to take out the No. 2 ranked player in the world. Not bad for a 40-year-old playing in her 21st US Open.

“I’m just Serena, you know,” Williams said.

There were some moments of doubt when Anett Kontaveit managed to make the greatest-of-all-time worry after losing the second set, but a quick break and a personal pep talk got Williams ready for the third set.

“I was just like, ‘Serena, you’ve already won. Like, just play, like, be Serena. You’re better than this.’ And that’s what I was able to do,” Williams said.

With fellow icon Tiger Woods in her player box, Williams upped her record to 42-0 in the first two rounds at the US Open and set up a third-round match with unseeded Ajla Tomljanovic.

But first, there will be a real treat Thursday night. For the first time ever, a first-round women’s doubles match will be played on Arthur Ashe Stadium in primetime. Serena will team up with her sister, Venus, as they begin their quest to win a 15th Grand Slam doubles title. 

“I’m super excited to play with her and just do that again. It’s been a long time,” Serena Williams said.

“More than anything, I just want to hold my side of the court up and, you know, be a good sister,” Venus William said.

But it’s not lost on the two of them the influence they’ve had on an entire generation of young tennis players.

“To see these young women living their dream, doing positive things in their lives and in turn influencing other young women, other people, not just young women,” Venus Williams said.

“I feel grateful that I can have that impact. I never thought I would have that impact, ever. I was just a girl trying to play tennis,” Serena Williams said.

Call it the “Serena Factor” — a record number of fans have been on the grounds for her first two matches, and an average of 2.7 million viewers were watching her Monday match at home. That’s four times as many as last year’s first round.