PRAGUE, Czech Republic -- No.9 seed Barbora Strycova emerged victorious in an all-Czech clash, eliminating 6th-seeded compatriot Katerina Siniakova in the quarterfinals of the J&T Banka Prague Open on Thursday, 6-1, 6-2.

"The first thing, I think, is that I was in the zone," Strycova told the media, after her win. "I was just focusing on what I have to do on the court, just on my game which was working very well, and I was moving very well."

All four of their prior matches had taken place on clay, with three of those four meetings going the way of Strycova. The 33-year-old improved the head-to-head lead over her 22-year-old countrywoman to 4-1 on Thursday, after a relatively smooth 69-minute encounter.

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World No.39 Strycova never faced a break point in the match, winning a superb 86 percent of points behind her first serve, and firing 13 winners to just nine unforced errors. Siniakova nearly matched Strycova in winners, but was undone by 24 unforced errors and dropped serve four times in the tilt.

"The movement was very good, and my serve was working well," Strycova stated. "Overall, I felt like I was playing pretty solid tennis."

Strycova has built a solid 10-4 win-loss record in Prague, making the semifinals for the second time after reaching the final four in 2017. The former World No.16 also posted back-to-back quarterfinal showings in 2015 and 2016.

The winner of the day’s last quarterfinal between Swiss qualifier Jil Teichmann and German lucky loser Tamara Korpatsch will meet Strycova in the semifinals on Friday.

"They must be playing very well, because Teichmann beat Svetlana [Kuznetsova], and [Korpatsch] was going through the qualies and playing really well against Schmiedlova," said Strycova. "So it’s going to be a battle -- it’s semifinals and that’s how it is, and I can’t wait to be there tomorrow."

Strycova put on a dazzling display to start the match, blasting down-the-line groundstrokes off both sides with ease as she opened up a big lead. By contrast, Siniakova struggled with unforced errors in the opening frame, as she lost her first two service games to cede a 4-0 lead to Strycova.

Siniakova found some much-needed consistency on her serve to avoid being bageled in the opener, but Strycova remained unfazed as she served for the set at 5-1. The No.9 seed fired a winning overhead to start the game and reached triple set point after a super serve was returned long. A wide return by Siniakova ended the set overwhelmingly in Strycova’s favor.

Siniakova put up a stern effort in the first game of the second set, fending off four break points, but a stirring forehand down the line gave Strycova a fifth opportunity to claim the game. That one was converted after a Siniakova forehand went wide, and Strycova was off to the races in the second set as well.

Strycova broke Siniakova again to garner a 4-1 lead, and the 33-year-old’s volleying skills were on point as she held at love to extend her lead to 5-1. Siniakova nearly squandered a 40-0 lead in the next game, sliding back to deuce, but held on for 5-2 and forced Strycova to take a shot at serving out the match.

It was only here where a minor crack appeared in Strycova's play, as she double faulted to fall behind 0-30. However, strong serving and deep groundstrokes pulled Strycova from there to match point. Strycova again double faulted, but used a big serve to attain a second match point, which she claimed after a netted error by Siniakova.