PARIS, France -- No.31 seed Mihaela Buzarnescu of Romania, making her French Open main draw debut, pulled off a shocking upset in the third round on Friday when she eliminated No.4 seed Elina Svitolina of Ukraine, 6-3, 7-5.

"I only wanted to be aggressive and wait for the good shots and just go for it, play angles and move on, move on in the court," Buzarnescu told the media during her post-match press conference. "Because, otherwise, she would just take advantage of every short ball that I was hitting."

"Of course, when you start seeing that you're kind of winning and leading in the match, thoughts are coming," Buzarnescu continued. "So I had some ups and downs, but I really managed to get through it and play a good match today."

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The 30-year-old Romanian had never won a main draw match in a Grand Slam event before this week, but she is now into the fourth round in Paris, capping a remarkable rise from an injury-bedeviled ranking of World No.377 just 12 months ago. This is also Buzarnescu's first victory over a Top 5 player.

It was a stunning display from Buzarnescu, who blasted 31 winners in the match to Svitolina's 11 during the 97-minute encounter. Svitolina was also undone by a whopping 29 unforced errors, and could only win 46 percent of points on her first serve.

Buzarnescu will face another top-tier challenge in the round of 16 when she takes on No.13 seed and 2017 US Open runner-up Madison Keys of the United States. Keys eased past No.21 seed Naomi Osaka of Japan earlier on Friday.

"She's really great player with aggressive game and good shots," Buzarnescu said of Keys. "But, you know, I'm just going to play my own game and just go on the court as a normal match against a player like me."

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It was a tremendous opening set from Buzarnescu, who quickly established a lead by breaking Svitolina for 2-1 with a scorching backhand winner down the line. The Romanian then held for 3-1 at love, closing the game out with an ace, proving that she was not intimidated by Svitolina’s status as a tournament favorite.

Svitolina had a chance to level the set, holding break point at 3-2, but failed to get her service return into play, and Buzarnescu used her effective forehand to hold onto her single-break advantage. The Romanian survived another tough service game by holding for 5-3 with an ace, forcing Svitolina to serve to stay in the set.

Svitolina could not achieve this goal. The Ukrainian dumped a backhand miscue into the net to give Buzarnescu break point, and a deep service return by the Romanian was returned into the net on the following point, putting her a set away from the upset. Buzarnescu dictated play in the opening frame, with 14 winners to Svitolina’s three.

Svitolina tried to turn the match around early in the second set, coming up with a break to lead 2-1. But Buzarnescu struck back immediately, crunching a crosscourt forehand to force an error from Svitolina while the Ukrainian was down break point, leveling the set at 2-2.

The No.4 seed, coming off her second straight Internazionali BNL d'Italia title, kept fighting, and was gifted a seemingly crucial break at 4-4 when Buzarnescu shockingly missed an overhead while down break point.

Svitolina then served for the set at 5-4, repelling a break point and reaching set point after two missed service returns by Buzarnescu. But Svitolina squandered the set point with a bizarre drop shot attempt that found the net, and on the following point, Buzarnescu nailed an overhead to bring up a second break point of the game. A Svitolina forehand miscue into the net evened the set at 5-5.

After a routine Buzarnescu hold for 6-5, Svitolina again had to face the pressure to serve to stay in the set -- and this time, in the match. Two game points went begging as Buzarnescu reached deuce with a volley winner, and the Romanian forced a netted error off of a slice backhand to bring up match point. One more Svitolina backhand mistake into the net gave Buzarnescu the classic upset.