Russian teenager Mila Andreeva reached the semi-finals of the French Open with the biggest win of her career against an out-of-form Aryna Sabalenka.
Sabalenka, the second seed, grimaced and pointed to her stomach while speaking to medical staff midway through the first set.
She continued to struggle and appeared to be considering retirement from the game.
Despite being far from her best, Sabalenka pushed through the discomfort to complete the match.
But it was Andreeva who emerged victorious, 6-7 (5-7), 6-4, 6-4.
At 17, she became the youngest player to reach a Grand Slam semifinal since Martina Hingis at the 1997 U.S. Open.
She will face Italy’s Jasmine Paolini in the quarterfinals, who stunned fourth-seeded Elena Rybakina earlier Wednesday.
“Honestly, I was really nervous before the match. I knew she had the advantage,” said Andreeva, who had lost her previous two meetings with Sabalenka in straight sets.
“Me and my coach had a plan for today, but again, I couldn’t remember anything. I just tried to play with my instincts.”
Andreeva uses Sabalenka’s struggles to her advantage
After being broken multiple times early in the opening set, it quickly became clear that Sabalenka was not in good form.
The Australian Open champion became increasingly frustrated with her below-par performance and called for a trainer after Andreeva broke to lead 4-3.
After speaking with the match doctor and returning to the court, Sabalenka made a gesture as if she was slapping her neck and appeared to announce her retirement.
But she seemed to bounce back, tying the set at 5-5 before battling it out in the tiebreak to take the first set.
But the same problems reoccurred for Sabalenka, who frequently had to crouch down to reposition herself on her racket and at one point was called for a timeout.
The 26-year-old appeared on the verge of tears for much of the second set and then walked slowly and listlessly to her seat when Andreeva broke at 5-4 to force the decider.
As the match went on for more than two hours, with both players struggling to hold serve, Sabalenka continued to receive treatment.
Andreeva, ranked 38th in the world, took advantage of her opponent’s struggles and scored a stunning lob on her second match point at 5-4 to seal a famous victory.