The WTA giant-killer is at it again.
Five-foot-three Dominika Cibulkova has made a career of beating big players on big stages.
A former world No. 4, Cibulkova has reached the quarterfinals or better at eight Grand Slams in her career, and became the first woman from the independent nation of Slovakia to reach a Slam singles final at the 2014 Australian Open.
She captured the biggest title of her career at the end of the 2016 season, when she won the season-ending WTA Finals in Singapore, and reached her career-best ranking last March.
Since then, however, she's struggled: Her ranking dipped to outside the world's Top 30 this year, but after two runner-up appearances in WTA events and a quarterfinal result at Wimbledon, the Slovak is back on the upswing.
After reaching the highest heights of her career, Cibulkova admitted after Saturday's third-round win over Wimbledon champion and No. 4 seed Angelique Kerber that she struggled with motivation after winning the WTA Finals.
"After winning Singapore, for me it was something unbelievable that, after that season, I was really flat," she said. "Even going for preparation for 2017, I was flat and I didn't feel motivated and ... I was just not there. I was struggling the whole year because I just felt the pressure and not even do the right things.
"I learned from my mistakes, and if I would be in the same situation, I know what I would do different and I will change some things for sure."
Fresh off the last eight at Wimbledon, Cibulkova is back in the second week of a Slam in New York after a trio of three-set wins over Arantxa Rus, Su-Wei Hsieh and Kerber.
It is her first time reaching the fourth round or better at back-to-back majors since the 2009 Australian and French Opens.
"I like to play on big stages -- the fans are helping always when you're winning. It gives you special energy," she said. "I was really working hard the whole year and the preparation before the year. I felt like I'm not getting the results that I want and I deserve for the way I play.
"It's just, you know, I won some more matches and it give me confidence. Tennis is all about mental and confidence. That's what I'm having right now. My hard work is paying off. I'm happy to show it on my best tennis on the biggest stage in the world."
Up next for the big-hitting Slovak is a round of 16 meeting that will no doubt be under a spotlight: She'll take on No. 14 seed Madison Keys, last year's US Open finalist.
The American lauded the "super feisty" Cibulkova in her own post-match press conference on Saturday: "She never gives up. I think she definitely goes for her shots and is pretty aggressive."
"[I've] never beaten her, so it's going to be another challenge. I'm going to come up with things to make things different than the matches before," Cibulkova said.
"I just want to play the way I play right now, and I'm still believing in myself. If I'm going to play well, I can beat Madison."
