BRISBANE, Australia - No.5 seed Karolina Pliskova put on an impeccable performance to defeat the unseeded Donna Vekic 6-3, 6-4 in the second Brisbane International semifinal.

The 2017 champion won 74% of her first serve points and struck 30 winners over one hour and 20 minutes, and was consequently rewarded with her third win over Vekic in four meetings - and the first in which she has not dropped a set.

"I felt like I have control about everything I am doing," Pliskova said afterwards. So comfortable does she feel, in fact, that she has not needed to call coach Rennae Stubbs down for an on-court coaching session in her last two matches. "If I would feel I really need help, I would call her maybe," Pliskova clarified. "But I just never felt like I really needed help - even though I was losing, I just felt I knew exactly what I have to change or what I have to improve."

It was the Croat, however, who seemed sharper in the opening stages. Repeatedly firing forehand winners - and the occasional backhand, too - down the line, she broke for 2-1 as Pliskova sent a forehand long.

Vekic has been speaking this week about her aim to improve the consistency of her serve in order to take advantage of its strength - but sadly, this was one of the elements that let her down today. There was no doubt that it could be a weapon at its best - in the second set, Vekic drew gasps as she hammered down three aces in one service game - but it would also be the 22-year-old's Achilles heel.

Leading 2-1, Vekic conceded her break thanks in part to two double faults and a smash over the baseline. Two games later, another double fault brought up break point for Pliskova to lead 4-2, which the Czech promptly took as a Vekic backhand found the net. And in the second set, a seventh double fault would put Vekic 2-3 down, the first break of the set.

Even when she got her second serve in, the World No.34 found herself at a significant disadvantage: in the first set, Vekic won only 38% of her second service points compared to Pliskova's 67%. It was in stark contrast to the 2016 US Open finalist's solidity. Three aces is far from Pliskova's most spectacular tally, but this relatively low number belied a service performance that was largely impregnable. Time and again, the former World No.1's delivery would set up a short ball that would be efficiently put far beyond Vekic's reach.

Off the ground, Pliskova's execution was clever and cool-headed. Favoring wrongfooting patterns when attacking, time and again the 26-year-old slotted the ball behind her opponent for a safer winner; when forced to defend, meanwhile, Pliskova used her backhand slice effectively to stay in points and gradually swing them towards offence - such as the sharply constructed rally that paved the way for her to break for 4-3 in the second set.

Afterwards, Pliskova was satisfied with her game and tactics. "I think I served well - maybe not that many aces, but still, I think I had a lot of points on the first serve," she mused. "I was happy with my movement today. I felt pretty good on the baseline. She can hit hard, but I managed to put a lot of balls back maybe more than she."

Closing it out was by no means simple for Pliskova, though. Serving to stay in the match, Vekic managed to respond to three net cords going against her by summoning up all her willpower to save three match points - two with brilliant forehands - and stay alive. And trying to serve it out, Pliskova oscillated between booming aces - and the double faults and loose errors that she had previously avoided.

But when a firm smash brought up a fifth match point for the World No.8, that was the final swing of the pendulum. Another Vekic backhand found the net, and Pliskova moved into the title round to face Lesia Tsurenko - against whom she has a 3-2 head-to-head lead.

Pliskova did not shy away from acknowledging that she will be the favorite in that match. "I think it's going to be a lot about me," she declared. "So it's like on one hand I know I can only lose it by myself, which is positive, but on the other hand, of course it's a little bit bigger pressure. But I've been in this situation many times, so I don't feel any pressure that I'm the seeded one that I have to win."

Indeed, Pliskova feels that she does not only embrace pressure - but needs it. "If I don't have it, I just don't try that much," she laughed. "So, of course, sometimes it can be a little bit like stressful or you can feel nervous that if you're not going to win they're going to talk about it and this stuff. But I think already I'm too old for thinking about others."