Tunisia's Ons Jabeur overcame a medical scare to battle into the second round of the US Open on Tuesday with a straight sets defeat of Colombia's Camila Osorio.

Jabeur, chasing a first Grand Slam crown after three agonising defeats in finals since 2022, opened her US Open campaign with a 7-5, 7-6 (7/4) victory on the Louis Armstrong Stadium.

The 29-year-old looked to be struggling during a tense first set, complaining to the chair umpire that she was having difficulty breathing after Osorio fought back from 4-1 down to level at 4-4.

Jabeur needed treatment from medical staff after going 5-4 down in the first set, and appeared to have her blood pressure taken during a timeout.

She then rallied to take the first set and appeared to poised to clinch victory after holding two match points in the second set while 5-3 up.

However Osorio rallied to stave off defeat, and went on to level at 5-5 after breaking Jabeur.

Jabeur broke back immediately to take a 6-5 lead but was then broken once again to send the second set to a tie break. 

Jabeur proved too strong for Osorio in the breaker, however, and will now face the Czech Republic's Linda Noskova in the second round.

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