NEW YORK, NY, USA -- No.29 seed Dominika Cibulkova of Slovakia pulled off a big upset in the third round of the US Open on Saturday, moving past No.4 seed Angelique Kerber of Germany, the 2016 US Open champion, by the scoreline of 3-6, 6-3, 6-3.

The frequent rivals know each other's games very well, as Cibulkova and Kerber had played each other 12 times previously. Reigning Wimbledon champion Kerber had the 7-5 edge in their head-to-head coming into this US Open match, including winning both prior meetings this season in straight sets.

But Cibulkova, whose best US Open performance is a quarterfinal showing in 2010, was the better player on the day by the match's conclusion, winning in two hours and 13 minutes. The diminutive Slovak overpowered former World No.1 Kerber, blasting 40 winners to the German's 23, and taking 62 percent of points on Kerber's second service.

"It feels pretty good and special," Cibulkova said, during her post-match press conference. "This year I lost to Angelique twice, and even during those matches, I was playing pretty solid. I was playing pretty fine. She just didn't give me any chance."

"We had to change something, and I think we had the great tactic with my coach, and I was able to do it," Cibulkova continued. "It was something that I don't usually do, but I was able to do it and it was working 100 percent."

"Of course, I was aggressive going for my forehand, going for my shots," the Slovak added. "Just overall everything was working."

Cibulkova will now face No.14 seed and last year's US Open finalist Madison Keys in the fourth round, after the American moved past Serbia's Aleksandra Krunic in three sets earlier on Saturday. Keys has defeated Cibulkova in all four of their previous meetings.

"Never beaten [Keys,] again, so it's going to be another challenge," Cibulkova stated. "I'm going to come up with things to make things different than the matches before. Yeah, I just want to play the way I play right now, and I'm still believing in myself today. If I'm going to play well, I can beat Madison."

"Her serve is very challenging for me, because she's kicking the serve," Cibulkova elaborated, regarding Keys. "I had the same thing before with Stosur, and now last three meetings, I was able to beat her. I'm sure I can find a way how to get there and how to play good tennis to beat her, to fight all the way."

Kerber broke Cibulkova in the first game of the match, as the players moved into a grueling first few games, replete with lengthy rallies befitting the two stellar movers. The Slovak was able to pull herself back level after a poor service game by Kerber at 3-2, which the German dropped at love after a double fault on break point.

But Kerber quickly reached triple break point in the next game, reclaiming the break advantage with a forehand crosscourt passing shot at the end of another long rally. The German took Cibulkova’s serve once more for good measure, erasing two game points for the Slovak at 5-3 and breaking again on her second set point, after a wide Cibulkova volley.

Nevertheless, it was Cibulkova who came out on fire in the second set, blasting her rocket groundstrokes to break Kerber twice in a row and lead 3-0. Cibulkova handed one of those breaks back at love in the next game, double faulting while down break point once more, but that would be the Slovak’s only misstep in the set.

Serving to stay in the set at 5-3, Kerber received a taste of her own medicine from the first set when Cibulkova dispatched multiple game points with more powerful play off the forehand side, and eventually broke after a wide backhand miscue by Kerber, leveling the tilt at one set apiece.

Cibulkova opened the decider by showing off her fighting spirit, fending off two break points and holding in the first game. This proved pivotal when Kerber threw in another shocker of a service game at 2-1, dropping serve at love to hand over a 3-1 lead to the Slovak.

Kerber continued to demonstrate the fight which brought her to three Grand Slam titles and the world’s top ranking, willing herself through a protracted battle to break back for 3-2 on her fifth break point of a high-octane game.

But after that tussle, Cibulkova came out from the changeover energized, and swiftly used her forehand to whip through another Kerber service game and break for the 4-2 lead. Cibulkova had no issues going forward, reaching match point at 5-3 behind a forehand winner, and converting it after coming out on top at the end of a crosscourt rally.