PARIS, France -- Sofia Kenin pulled off a stunning upset in the third round of Roland Garros on Saturday, defeating her fellow American, three-time champion and No.10 seed Serena Williams, 6-2, 7-5.

"Serena is such a tough player," Kenin said, in her post-match press conference. "I'm still trying to process what just happened. I knew before the match, I was ready to go. I was there to win a match. Of course she's a true champion and an inspiration and she's done amazing things for American tennis. I'm just really happy with this win. I played really well, and I'm just excited for my next match."

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The 20-year-old earned her spot in the fourth round of a Grand Slam event for the very first time in her career after carving her way through a 92-minute victory over the legendary 23-time Grand Slam champion, in their first meeting. It is Kenin's first Top 10 win of the year, and the third victory over a Top 10 player in her career.

"I think this is such a great win for me," Kenin stated. "I mean, as you can see after the match -- I don't normally cry after a match. I had so many emotions playing on Chatrier. I have always imagined playing there and winning a match. I went there today with the mentality to go and win."

Kenin, just outside of the seedings at a ranking of World No.35, had reached the third round of the US Open in the last two years, but had not won a match in the Parisian major prior to this year. Kenin, however, had risen in stature during 2019, winning her first WTA singles title in Hobart in January and peaking at a career-high ranking of No.33 in March.

The unseeded American notched 61 percent of points off of the vaunted Williams second serve, and only allowed herself to be broken once out of Williams's seven chances. Williams had 30 winners to Kenin's 23 during the clash, but the long-time former World No.1 was undone by 34 unforced errors, exactly twice as many as Kenin fired in the match.

"I definitely knew after the first set, you know, she's Serena for a reason and she's gonna come up with some amazing shots," said Kenin. "I actually did feel like, okay, Serena is getting there, she's on a roll, and I knew I had to somehow stop it."

"Closing out the match, you know, you get a lot of things processed in your head," Kenin added. "I just had to somehow just try to put them aside and close out the match. And, yeah, if I would have lost, it would have been pretty heartbreaking. I did everything I can to win, and I'm just really proud of myself."

Kenin will face No.8 seed Ashleigh Barty of Australia in the round of 16, after Barty defeated Andrea Petkovic concurrently with the Kenin/Williams match, by the scoreline of 6-3, 6-1. Barty leads their head-to-head by 2-0 (4-0 in sets).

"[Barty is] a tough player, she's very crafty," Kenin admitted. "It's not going to be an easy match. I'm just going to go out there and leave everything out, play my best game, and I think if I play well, good things can happen, and I believe in myself."

Kenin had a look in the Williams service games straight away, as the 23-time Grand Slam champion had to come up with clutch serves to stave off a break point and hold in the opening game of the tilt. Kenin was unfazed by her missed chance, as she held at love twice consecutively to reach 2-2.

The unseeded American cracked the opening frame open in the following game, gutting out the first service break of the match by deploying a winning dropshot on her fifth break point, to claim a 3-2 lead. Kenin did well to prevent Williams from breaking back straight away, fending off a break point to hold for 4-2.

Kenin maneuvered through two more close games to obtain the one-set lead, as she continued to use the dropshot to disrupt the powerful Williams game and found winning passing shots whenever she could. Kenin earned the double break lead at 5-2 with a forehand winner, then evaded a final break point before holding to clinch the opener.

The second set was far more competitive, though Kenin seemed to quickly carry over the momentum from the opener, breaking Williams at love to start. But, finally, Williams converted a break point for the first time all day when a wide backhand by Kenin allowed Williams to pull back level at 3-3.

The combatants had at last reached simultaneous groundstroke strength, as they batted the ball at each other with increased intensity to earn service holds through to 5-5. But Kenin exhibited the grit which belies her young age late in the set, slamming a return winner to break Williams for a fourth time, and garner a chance to serve out a famous victory.

Williams can never be counted out at any point in a scoreline, and found herself holding a break point in the final game. But a wide forehand miscue by the 23-time major-winning legend cost her that chance, and Kenin, using her beautiful backhand as the bedrock for her game, closed out the win on her second match point.