Defending champion Iga Swiatek was pushed to the brink by fellow four-times Grand Slam champion Naomi Osaka but secured a 7-6(1) 1-6 7-5 victory after saving a match point in a high-voltage second-round match at Roland Garros on Wednesday.
Top seed Swiatek's clay prowess makes her a firm favourite against anyone but the 22-year-old, who entered the contest on the back of 13 wins and titles in Madrid and Rome, faced huge pressure and was a point away from dropping the first set.
In testing conditions under the roof on Philippe Chatrier, the powerful Osaka posed a litany of problems in one of her best matches since coming back this year from a maternity break, but did not capitalise while up 40-30 at 5-4, hitting a shot long.
Three-times champion Swiatek raised her level and ran away with the opening set in the tiebreak but the Pole found herself trailing 4-0 in the next set as the 26-year-old Osaka shrugged off any disappointment to comfortably level the contest.
Osaka saved two break points to hold at the start of the decider and fired a sublime backhand crosscourt winner in the next game to pounce for a 2-0 lead, which the Japanese player extended on serve after another almighty battle.
A rattled Swiatek clawed her way back from 5-2 down and saved a match point before taking full advantage of late errors from a nervy Osaka's racket to complete a famous victory and avoid her earliest exit from the Grand Slam.