Karolina Pliskova, into her first major semifinal, is getting the hang of this breakthrough thing

NEW YORK—Just after her 6-2, 6-2 win over Ana Konjuh, which took all of 57 minutes, Karolina Pliskova was asked how she felt. The 24-year-old Czech didn’t waste any time with her answer.

“It’s an amazing feeling,” she began in her rapid-fire, no-time-to-take-a-breath English.

She then went on to tell us that she loves New York, loves the hard-court season and didn’t think her opponent played her best, but does think we’ll be seeing a lot more of her in the future. All of that information, if you could keep up with it, was delivered in under five seconds flat.

Pliskova talks quickly, but she was especially revved up on Wednesday, and it was easy to understand why. After building a reputation as the sport’s most conspicuous Grand Slam underachiever, she had reached her first semifinal at a major. Two days before, she had reached her first Grand Slam quarterfinal. Four days before that, she had reached her first Grand Slam round of 16. And a week prior to the Open, Pliskova had won the biggest title of her career, in Cincinnati.

She’s getting the hang of this breakthrough thing.

“It was a big step and a big success,” Pliskova said of her performance in Cincy, which included blowout wins over world No. 3 Garbiñe Muguruza and world No. 2 Angelique Kerber. “I took a lot from that week. I’m really happy I took it here with me in New York, and it’s paying even more.

“I was struggling a little with my game [at] the Grand Slams. I knew I can play big tennis and good matches, but I couldn’t just, you know, put it in the Grand Slams. I felt [a] little pressure on myself. [I’m] happy right now it’s all paid off, and I finally [found] my game.”

At its best, Pliskova’s game is icily awe-inspiring. A rangy 6’1”, she has a natural, no-wasted-motion service that has produced 466 aces this season, nearly 200 more than any other WTA player. Pliskova’s ground strokes are just as efficient, and when they’re clicking, just as lethal.

It’s hard to think of a player whose timing is as pure as hers. With little noticeable effort, and with hardly any knee bend, Pliskova makes contact and the ball takes off, supercharged, on a line; if she has hit it well, it doesn’t come back. Over the course of two points late in her fourth-round win over Venus Williams, Pliskova put the ball on or within an inch of the baseline half a dozen times.

Like so many power players, though, the fact that Pliskova can hit these types of high-risk, high-reward shots leads her to try to do it too often for her own good. Watching from the outside, it doesn’t look like she does much to adjust. Whether she’s winning or losing, Pliskova moves quickly between rallies and tries to end them as soon as she can. Of the 93 points that she and Konjuh played, 64 of them were over in four shots or less.

Pliskova says she has improved her return of serve, and that she’s working on her movement, but it’s still “not great.” Typically, though, when a talented player has a breakthrough, it happens in the mind. Pliskova, a noted racquet smasher, says that has also been the case with her.

“I was more angry before with myself on the court,” she said on Wednesday. “So that I [have] improved a lot. Sometimes I’m still smashing my racquets, more in the practices than in the matches. I’m trying to be calm in the match because it’s not really helping me.”

Ironically, the big audiences in Ashe Stadium have had a hand in helping her stay composed. In her win over Williams, Pliskova didn’t want to give the 23,000 people rooting against her any sign of vulnerability. She knew they would pounce.

“I don’t want to show even the opponent, and even the crowd and the people, any frustration,” Pliskova said.

Pliskova will ascend to a career-high No. 6 next week. Having her stay there would be good news for the WTA. At her best, she plays jaw-dropping tennis that belongs in the Top 10, and in the semifinals of the U.S. Open.

Pliskova plays fast and talks faster, and her rise from Grand Slam also-ran to overachiever has been meteoric. That’s just how she does things.

“There are people saying that I could be there earlier,” she said, “but right now I feel great, and I feel it’s the right time for having results like this.”