The second-seeded Świątek, a former world No. 1, lost to the 50th-ranked Linette in three sets, 6-1, 5-7, 3-6.
Świątek, who had a first-round bye, exited a tournament after her opening match for the first time since August 2021, Polish state news agency PAP reported.
It was their second meeting at a WTA-level event. Linette avenged her loss to Świątek in Beijing in 2023, where she was beaten 1-6, 1-6.
The victory ranks among the biggest of Linette’s career. She previously defeated then-world No. 1 Ashleigh Barty in 2021, and last year in Miami she beat third-seeded American Coco Gauff in the fourth round.
Świątek last lost her opening match at a tournament on August 19, 2021, in Cincinnati, where she fell to Ons Jabeur 3-6, 3-6 in the second round.
The six-time Grand Slam champion has now exited Miami in unexpected fashion for the second consecutive year. In 2025, she lost in the quarterfinals to Alexandra Eala, then ranked No. 140 in the world.
Eala, now seeded 31st, will face Linette in the third round on Saturday.
(gs)
Source: IAR, PAP