Unseeded Ekaterina Alexandrova and Tereza Martincova will square off for a berth in the Agel Open semifinals after both defeated seeded players in Round 2 matches on Thursday.

Leading 7-6(3), 1-0 against No.2 seed and defending champion Anett Kontaveit, Martincova advanced when the Estonian retired with a low back injury, and Alexandrova closed the day's slate with a 6-1, 7-6(1) win over No. 5 seed Daria Kasatkina.

Learn more about how they set up their sixth career head-to-head meeting, by the numbers.

Ostrava: Alexandrova beats Kasatkina to extend win streak to seven

1: Though the match was cut short, the win over Kontaveit was Martincova's first career Top 10 win. Her previous best win by ranking was a triumph against then-No.11 Kiki Bertens at the 2021 Dubai Duty Free Tennis Championships.

2: Martincova is bidding for her second semifinal of the year in her third quarterfinal appearance. She also reached the semifinals in Nottingham, and lost in the quarterfinals in St. Petersburg.

3: Martincova is one of three Czech players remaining in the draw, but the only one left in the top half. Wildcard Karolina Muchova lost her Round 2 match earlier on Thursday to American qualifier Caty McNally, who'll be the next opponent for No.1 seed Iga Swiatek.

58: The first set of the match between Kontaveit and Martincova lasted 58 minutes. Martincova led 3-0 early and then lost four straight games to fall behind by a break. She got the break back immediately, and the pair stayed on serve until the tiebreak.

39: Despite Kontaveit's injury concerns, the two players combined for a high-quality set-plus. They combined to hit 39 winners (with Kontaveit totaling 26) and just 28 unforced errors (Kontaveit hit 21). In addition, Martincova landed 82% of her first serves, while Kontaveit landed 69%.  

2013: Alexandrova leads Martincova in their overall head-to-head, 3-2, and their head-to-head dates back nearly a decade. They first played at an ITF World Tennis Tour event in Kazan, Russia in 2013, and their first three meetings went three sets. Alexandrova's won the last two, both in St. Petersburg, in straight sets in 2019 and 2021.


5: Alexandrova will be contesting her fifth quarterfinal of the season, and she's 4-0 in that round this year. She reached the semifinals in Charleston and Madrid, and won the titles in 's-Hertogenbosch and Seoul. 

6: Alexandrova won six straight points from 1-1 in the second-set tiebreak to seal victory against Kasatkina. Earlier in the set, she was 3-1 down.

97: Alexandrova needed 97 minutes to defeat Kasatkina, and the second set was nearly three times as long as the first. She captured the opening set in 28 minutes, but needed 69 minutes to claim the second set. 

Parks upsets Sakkari to continue breakthrough in Ostrava

7: Alexandrova has now won seven straight matches. Fresh off winning her third career Hologic WTA Tour singles title in Seoul, South Korea, she arrived in Ostrava and defeated former World No.1 Victoria Azarenka for the first time in Round 1 before upsetting Kasatkina.

19: Alexandrova's win against Kasatkina was her 19th career Top 20 victory. 

46: Kasatkina struggled on serve in the match, landing only 46% of her first serves.

45: Meanwhile, Alexandrova was the more aggressive player in the match, as she totaled 45 winners and 35 unforced errors in victory. Kasatkina totaled just 11 winners and 15 unforced errors. She also broke Kasatkina's serve six times.