MIAMI -- No.16 Ekaterina Alexandrova ended Iga Swiatek's quest for a second sweep of the Sunshine Double, defeating the World No.1 6-4, 6-2 in the Miami Open Round of 16 on Monday night. The victory is Alexandrova's first career win over a reigning World No.1 and puts her into her third WTA 1000 quarterfinal.

A quarterfinalist in Miami last year, Alexandrova will face No.5 Jessica Pegula on Wednesday. Pegula advanced to her third consecutive Miami quarterfinal by defeating No.20 Emma Navarro 7-6(1), 6-3. 

Alexandrova overpowered Swiatek from the service line and the baseline to notch her second win over the Pole. Alexandrova posted her first win by the same scoreline at the 2021 Melbourne 500, but Swiatek had won their three meetings since.

"We played quite a few times before and sometimes it was three sets," Alexandrova said. "I think sometimes I was quite close to it but still far away. Winning against her, of course it feels great. I'm not sure if it's a surprise or not, but I just worked quite hard on the court and it paid off."

Coming off wins over Donna Vekic and Anastasia Pavlyuchenkova, Alexandrova broke Swiatek in the opening game and never looked back. Her first serve and forehand flummoxed Swiatek, who had no answers for her placement, power and precision. Swiatek generated just one break point in the match but Alexandrova saved it to extend her first-set lead to 4-2. 

Alexandrova closed out the 49-minute opening set with a decisive love hold. She struck 17 winners to 17 unforced errors, while Swiatek struck eight winners to 16 unforced errors. 

"Just trying to go more inside the court, trying to hit everything in front of you so the opponent doesn't have as much time," Alexandrova said. "I think when it goes in its very good but sometimes it's not working. But today it worked."

Alexandrova stuns Swiatek in Miami to notch first win over World No.1

Swiatek came from a set down to defeat 26th seed Linda Noskova 24 hours earlier, but she struggled to find any traction on Monday night. Despite serving at 71 percent of her first serves in, Swiatek was broken three times in the match. Coming off her win at the BNP Paribas Open, Swiatek was bidding to become the second woman to sweep both tournaments twice, having done so in 2022. 

"Disappointed for sure because I thought I was going to play better here in Miami," Swiatek said. "But she played an amazing match and for sure, she was the better player out there today. Her serve, I had a had time reading it. I got a little bit tense when I couldn't return well."

Alexandrova rode her power game through the second set to notch her 13th career win over a Top 10 opponent. She finished the match with 31 winners to 27 unforced errors. Swiatek hit just 11 winners to 27 unforced errors. 

"Second quarterfinal here, second year in a row," Alexandrova said." Beating Iga after so many tries and she's No.1. It's the first time I beat No.1. All three things are very special to me."