Ekaterina Alexandrova won a grueling match between qualifiers at the Mutua Madrid Open on Monday, taking over three hours to overcome Marie Bouzkova 6-7(4), 6-0, 7-5 and reach the quarterfinals of the first WTA 1000 clay-court event of the year.

In the quarterfinals, Alexandrova will meet Amanda Anisimova, who staved off a second-set comeback by former World No.1 Victoria Azarenka and held on for a 6-1, 6-4 victory.

Ekaterina ekes out a win: Alexandrova's win over Bouzkova featured numerous twists and turns during its 3-hour and 4-minute running time, as the pair tussled for a spot in their first WTA 1000 quarterfinal of the season.

The World No.45 Alexandrova misfired on her first four match points before finally converting her fifth chance, improving to 2-0 over 77th-ranked Bouzkova.

Highlights: Alexandrova def. Bouzkova

"It was super tough, and she played so well," Alexandrova said afterward. "It was kind of impossible to finish the points, because she was everywhere. Every ball I hit, she's hitting back."

Alexandrova, the No.1 seed in last week's qualifying rounds, could only convert seven of her whopping 22 break points, but that would be enough to get past Bouzkova.

Alexandrova had 44 winners from her forehand side, to just five forehand winners by Bouzkova. However, Alexandrova had to survive her 80 unforced errors in the match, more than double Bouzkova's total.

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Topsy-turvy tilt: The tone of the match was solidified at 3-1 in the first set. Bouzkova held serve in a 21-minute game that featured 12 deuces and saw her withstand nine break points, any one of which lost would have put her down a double-break.

On one of those break points, Bouzkova rifled a down-the-line winner to extend the game in an early contender for shot of the month:

Shot of the year? Watch Bouzkova's forehand stunner in Madrid

Bouzkova turned the set around from there, coming back to reach a tiebreak, which she grabbed to take the one-set lead after 84 minutes of play.

Alexandrova wrested the momentum back. The second set featured break points in each of the first four games, but Alexandrova gritted out all of those games, eventually earning the bagel.

In the third set, Alexandrova garnered a pivotal break for 5-3 with incredible depth, and served for the match. But Alexandrova squandered three match points in that game with an unforced error and two double faults, allowing Bouzkova to break back for 5-4.

Alexandrova held a fourth match point in the following game as well, but she hit a netted miscue, and Bouzkova got back completely level at 5-5.

Alexandrova, though, played some of her most powerful and creative tennis to save two break points in the next game and hold for 6-5, turning the momentum back in her favor. At last, Alexandrova converted her fifth match point with a blistering forehand return winner.

Amanda advances: World No.33 Anisimova continues a resurgent season with her 1-hour and 21-minute win against No.15 seed Azarenka. In January, the 20-year-old won her second career title at Melbourne Summer Set 2 before reaching the Round of 16 at the Australian Open.

Anisimova dominated proceedings early before quelling a late charge by two-time Grand Slam champion Azarenka. Anisimova is now into the Madrid quarterfinals in just her second main-draw appearance at the event.

"I think it was a really tough match, but I was playing well throughout all of it," Anisimova said afterward. "It was my first time playing [Azarenka] so I was really excited, and I'm just happy to get this win.

"It feels a lot better winning a match with those challenges in the end, as opposed to if it was an easy match. Getting through that and not letting her come all the way back, it just helps me with my confidence."

Highlights: Anisimova def. Azarenka

Anisimova had a commanding 6-1, 5-1 lead and held three match points in that game, but steely Azarenka proceeded to win three games in a row and put extra pressure on the unseeded player. But Anisimova recovered her big groundstrokes, powering to triple match point at 5-4.

Anisimova misfired on two more match points, but she slammed an ace on her sixth overall to take home the victory and move into a quarterfinal matchup with Alexandrova.

In their only previous meeting, Anisimova defeated Alexandrova in straight sets at Doha in 2020.