Iga Swiatek edged past Danielle Collins to book her place in the semi-finals of the Paris Olympics. (Full Olympics Coverage | More Sports News)
The top-ranked seed was pushed all the way by her American opponent, but came through a third-set decider to win 6-1 2-6 4-1 after Collins was forced to retire.
Swiatek asserted her dominance early on, racing into a 3-0 lead and remained in control for the rest of the first set, with Collins no match for the Pole.
However, Collins started with a three-game lead of her own in the second set, looking a completely different player to the one who first stepped out on Court Suzanne Lenglen.
The world number one did have two chances at 5-2 down to put the pressure back on her opponent, but Collins remained composed to take the game to a deciding third set.
But Swiatek would find her rhythm once again, racing into a four-game lead as Collins took a medical timeout off-court.
The American would emerge back on court to win her first game of the set but retired immediately after, handing the win to her opponent.
Swiatek will continue her quest for a fifth success at Roland-Garros on Thursday where she will face Zheng Qinwen, who beat Angelique Kerber.
Data Debrief: Swiatek marches on, just
Swiatek's love affair on the clay courts in the French capital continued, but it did not come without its nervy moments.
Despite dominating the opening set, Collins was impressive with her serve, scoring seven aces in the contest compared to Swiatek's two.
Swiatek's triumph saw her become the first Polish player in history to reach the Olympics semi-finals in the singles.
