Ashleigh Barty’s brave bid to cut short Serena Williams’ grand slam comeback has ended in a tense three-set French Open defeat for the Australian No.1.

Barty appeared to be careering towards a famous victory before letting slip a one-set advantage in the 3-6 6-3 6-4 second-round loss in Paris.

Seemingly unnerved by the occasion, Barty broke the 23-times major champion early in the second set to surge further ahead before Williams willed her way back into the enthralling contest on Court Philippe-Chatrier.

Barty’s game plan to move Williams from side to side in the hope of exhausting the underdone champion in just her sixth match back since giving birth last September initially paid dividends.

But the grand slam colossus drew on her unrivalled fighting qualities – and energy reserves many doubted she still possessed at almost 37 and eight months into motherhood – to stave off Australia’s 17th seed after one hour and 46 minutes.

Barty’s exit leaves former finalist Samantha Stosur and 24th seed Daria Gavrilova to fly the Australian flag.

Stosur, runner-up at Roland Garros in 2010 and a semi-finalist in 2009, 2012 and 2016, is through to the third round for the 10th straight year.

The veteran clay-court star plays 2016 champion Garbine Muguruza in a repeat of their semi-final two years ago after denying doubles partner Anastasia Pavlyuchenkova 6-2 7-6 (7-1) earlier on Thursday.

Gavrilova saved a match point in snatching a 5-7 7-5 6-3 victory from the jaws of defeat against American Bernarda Pera.

The great escape set up a return clash with Belgian 16th seed Elise Mertens, who eliminated Gavrilova from both last year’s French Open and the Australian Open in January.