Five-time major champion Iga Swiatek was on the end of a monumental shock as Filipina teenager Alexandra Eala continued her dream run to reach the Miami Open semi-finals.

Second seed Swiatek, playing with increased security in Miami after being verbally abused by an "aggressive and taunting" fan, was completely out of sorts as she lost 6-2 7-5 to the world number 140.

The 23-year-old's serve was broken eight times as she continually struggled to hold serve, while her baseline game was shaky and led to a host of forehand errors.

Eala, 19, remained composed and focused as she completed the biggest win of her career.

"It might be one of the biggest upsets I've been on the side of the court for," said former British number one Tim Henman, watching in his role as a Sky Sports analyst.

Poland's Swiatek recently spoke out about the emotional toll she has faced in recent months, having served a one-month ban for a doping offence and not wanting to "step on the court" as a result.

This defeat means she has not reached a final since winning the French Open in June.

Eala, who was given a wildcard to play in Miami, will play American fourth seed Jessica Pegula in the semi-finals after she defeated Britain's Emma Raducanu.

Next week Eala will break into the world's top 100 for the first time.

"My mind is really blank, I don't think I've processed what I've just done," Eala told Sky Sports afterwards.

"In the end I'm still the same player I was two weeks ago."

Coming from a country with little tennis pedigree, Eala is already accustomed to being a trailblazer for the Philippines - even though she is still a teenager.

In 2021, she became the first Filipina to win a WTA Tour match and first to win a junior Grand Slam crown with the 2022 US Open title.

The New York triumph even led to the teenager gracing the cover of Vogue back home.

Now Eala has announced herself to a wider global audience, having beaten some of the biggest names on the WTA Tour to reach the last four.

A graduate of the Rafael Nadal Academy, she had only won two main-draw matches before her stunning run on the Miami hard courts.

Three of her four victories at the WTA 1000 event - the tier of tournaments below the Grand Slams - have come against major champions.

A second-round win over 2017 French Open champion Jelena Ostapenko was followed by a seismic win over world number five Madison Keys - who won the Australian Open in January - in the third round.

Eala received a walkover in the fourth round when Spanish 10th seed Paula Badosa withdrew injured, but showed again why she is regarded as an emerging star in Wednesday's quarter-final.

Fearless, ferocious and hitting a flurry of winners, Eala produced a quality performance in her first career match against Swiatek.

However, they had met previously when Swiatek, along with 22-time major champion Nadal, presented Eala with her graduation certificate two years ago.

"It's so surreal," added Eala, who had Nadal's uncle and former coach Toni, with her team against Swiatek.

"I'm so happy and so blessed to be able to compete with such a player on this stage.

"My coach told me to run, to go for every ball, to take all the opportunities I can, because a five-time Slam champion is not going to give you the win."

In the men's singles, German top seed Alexander Zverev was knocked out by France's Arthur Fils in the fourth round.

Zverev lost 3-6 6-3 6-4 to 17th seed Fils, leaving only Taylor Fritz and Novak Djokovic as the remaining top-10 seeds in the last eight.

Fourth seed Djokovic had been scheduled to play his quarter-final against American 24th seed Sebastian Korda later on Wednesday.

However, the match was pushed back to Thursday to avoid breaching ATP rules prohibiting matches beginning after 23:00 local time.

Miami Open organisers said that the game will be the third match from 13:00 (17:00 GMT).

The winner will face Bulgarian 14th seed Grigor Dimitrov, who produced a remarkable mental and physical effort to beat Argentina's Francisco Cerundolo.

Dimitrov, 33, could not convert any of seven set points in the first set, and looked exhausted in the latter stages, before securing a 6-7 (6-8) 6-4 7-6 (7-3) win.

Moments after victory he was breathing heavily and assessed by a doctor on his chair.

British pair Julian Cash and Lloyd Glasspool reached the men's doubles semi-finals with a 7-6 (7-1) 3-6 10-8 win over India's Yuki Bhambri and Portugal's Nuno Borges.