Two-time Wimbledon runner-up Ons Jabeur retired during her first-round match Monday because of difficulty breathing, the latest issue for her during an injury-filled season.

The 30-year-old was forced to pull out while training 6-7 (5-7) 0-2 against Viktoriya Tomova.

Jabeur was visited by a trainer for a medical timeout in the first set.

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At one point, she sat on her sideline seat and cried into a towel.

“I wasn’t expecting not to feel good. I have been practising pretty well the last few days but I guess these things happen,” Jabeur said.

“I’m pretty sad. It doesn’t really help me with my confidence and what I keep pushing myself to do, even though it was a very tough season for me.

“So I hope I’m going to feel better and we’ll see what’s going to happen.”

Jabeur lost to Elena Rybakina in the 2022 final and to Marketa Vondrousova in the 2023 final.

She also was a finalist at the 2022 US Open, losing to Iga Swiatek.

Jabeur’s 2024 season ended early because of a shoulder injury and she’s dealt with leg problems this year, now sitting outside the world’s top 50.

She said she will “definitely try to disconnect a little bit from tennis”.

“Try to just enjoy life outside tennis, recover and spend a little bit of time with the family and hopefully that could recharge me,” Jabeur said.

“Definitely ‘rest’ is the word for it.”

Elsewhere in the first round, last year’s runner-up Jasmine Paolini recovered from losing the opening set to beat Latvian world No. 402 Anastasija Sevastova 2-6 6-3 6-2.

Home hero Katie Boulter defeated ninth seed Paula Badosa 6-2 3-6 6-4 on Centre Court for one of the biggest wins of her career, perhaps giving her Australian fiance Alex de Minaur a fillip ahead of his opening match on Tuesday.

It was a good day for the host nation with rising star Sonay Kartal also notching a shock, defeating 20th seed and former French Open champion Jelena Ostapenko 7-5 2-6 6-2.

Emma Raducanu won too and will now meet the 2023 champion Marketa Vondrousova, who beat 32nd-seeded American McCartney Kessler 6-1 7-6 (7-3).

Australian Open champion Madison Keys survived a scare, the American coming from a set down to scrape past Elena-Gabriela Ruse 6-7 (4-7) 7-5 7-5.

Seeds Elina Svitolina (14) and Amanda Anisimova (13) also progressed, the latter handing out a ‘double-bagel’ 6-0 6-0 defeat to Yulia Putintseva.