Serena Williams has 'a little left in me' after US Open win. Doubles, third round up next

Serena Williams' victory lap continues. 

The 40-year-old defeated No. 2 seed Anett Kontaveit in the second round of the U.S. Open on Wednesday night, prolonging her legendary career after announcing plans to "evolve away" from tennis following the year's final Grand Slam.

Her high-level performance looked far from a swan song. "It’s no rush … I’m loving this crowd. It’s really fantastic. There’s still a little left in me," Williams said afterward.

Williams will play at least one more match at the U.S. Open. She is set to face Australia's Ajla Tomljanovic in a third-round matchup on Friday, but first she will reunite with sister Venus Williams to play doubles on Thursday.

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Serena Williams does it again with second-round upset of No. 2 seed

Williams entered Wednesday's matchup against Kontaveit an underdog, but she reminded everyone that she's still "a pretty good player." She upset Kontaveit 7-6, 2-6, 6-2.

Williams went the distance to win the first set 7-6 (7-4) after a thrilling tiebreaker. The boisterous crowd got to its feet applauding Williams, including Tiger Woods who triumphantly pumped his fist alongside her family. The first set lasted 1 hour and 3 minutes.

It was a different story in the second set. Kontaveit jumped to an early two-break lead over Williams and easily grabbed the second set, 6-2.

"After I lost the second set, I thought, 'Oh my goodness, I got to give my best effort because this could be it,' " Williams recalled. "I just wanted to keep trying and see what I can do and just do my best. I was just really excited."

But Williams' competitive nature kicked in during the decisive third set, where she only dropped two games. She gave her signature twirl to the deafening crowd.

Serena Williams is having fun

Following a first-round exit at the Cincinnati Open earlier this month, Williams said she's finally playing up to the high level she's been practicing.

"I haven’t played many matches but I’ve been practicing really well," she said. "In my last few matches it just wasn’t coming together. I’m like, ‘This isn’t me!’ The last couple matches here in New York it has really come together."

What's different? She said she's having fun just playing.

“I’m super competitive. I’m just looking at it as a bonus," Williams said. "I don’t have anything to prove. I don’t have anything to win. I have absolutely nothing to lose. Honestly, I’ve never got to play like this since '98. Literally, I’ve had an ‘X’ on my back since '99, so it’s kind of fun … It’s been a long time since I’ve been able to do that."

An introduction fit for a queen

Williams got a "Queen of Queens" introduction Wednesday. Before she took the court at Arthur Ashe Stadium, a video tribute narrated by Queen Latifah was played. The video included some of the star's greatest highlights from the U.S. Open, which she's won six times (1999, 2002, 2008, 2012, 2013 and 2014).

One of the moments included was Williams falling into a split after winning a point against Bethanie Mattek-Sands in the third round of the 2015 U.S. Open.

Tiger Woods and more celebs pack the stands

Two nights after a who's who of celebrities descended upon Arthur Ashe Stadium for Williams' first-round matchup, the star power returned on Wednesday night.

Tiger Woods, Zendaya, Spike Lee, Roger Goodell, P. K. Subban and more stars were on hand to see what could have been Williams' final match of her legendary career.

Woods sat in Williams’ player's box and was greeted by Venus Williams during the first set. They were joined in Williams' box by her husband, Alexis Ohanian, her mother,  Oracene Price, and Vogue editor-in-chief Anna Wintour. It was Vogue that carried the Serena cover announcing she was "evolving away from tennis." Serena long has been a fashion icon and has walked many red carpets, including the Met Gala, which is organized by Vogue.

Following Williams' win, Woods tweeted: "It was a privilege to watch greatness. Congrats @serenawilliams."

Kamala Harris, Stephen Curry, more react to Williams' win

Politicians, sports stars and celebrities that weren't able to attend the U.S. Open in person took to social media to celebrate Williams' win and applaud her effort.

"Thank you @SerenaWilliams for inspiring people around the world with your talent, grace, and determination both on and off the court," Vice President Kamala Harris tweeted. "We celebrate all that you have been, all that you are, and all that is to come."

Stephen Curry, fresh off his graduation from Davidson College, tweeted: "Not done yet."

'NOT DONE YET': Tiger, Steph Curry, more stars react to Serena's win

Williams will hit the court again during doubles opener with Venus Williams

Williams will take the court at Flushing Meadows with sister Venus Williams on Thursday in a first-round matchup against the Czech Republic's Lucie Hradecka and Linda Noskova at about 7 p.m. ET in Arthur Ashe Stadium.The matchup will mark the first time a first-round doubles match will air during prime-time.

The sisters have 14 doubles Grand Slam championships, tied for second in the Open Era, including two at the U.S. Open, in 1999 and 2009. Their most recent doubles Grand Slam title was at Wimbledon, in 2016. They also have three Olympic gold medals in doubles.

"I’m so excited for doubles," Williams said. "It’s been so long, we got to bring the reunion back. I’m excited to play with Venus and get some more practice."

Venus Williams is out of the singles competition. She lost 6-1, 7-6 (7-5) to Alison Van Uytvanck of Belgium in the first round.

Who is up next?

Williams will face Ajla Tomljanovic of Australia on Friday in a third-round matchup.

The two have never played each other.

This article originally appeared on USA TODAY: Serena Williams wins at US Open. Doubles, third round up next