Ashleigh Barty is stewing over what might have been after her brave bid to cut short Serena Williams' grand slam comeback ended in a tense three-set French Open defeat.
Barty led by a set and a break before falling 3-6 6-3 6-4 to the returning grand slam colossus.
"It's disappointing because I was well and truly in the match. And I felt off the baseline I was no issues at all," Barty said.
"I would love to have five or six forehands again, a couple of those errors, and a couple more first serves.
"It could be a different outcome."
The match between tennis' two comeback queens turned the instant Williams released a primal roar after blasting a backhand return winner after being broken in the opening game of the second set.
The stadium-shuddering release of frustration sparked an adrenaline surge that carried Williams all the way to victory.
"When push came to shove, the real Serena came out," Barty said after the the 23-times grand slam winner set up a third-round date with German 11th seed Julia Goerges.
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 Williams drew on her unrivalled fighting qualities - and energy reserves some doubted she still possesses at almost 37 and eight months into motherhood - to stave off Australia's 17th seed after one hour and 46 minutes.
"I feel like I wasn't really doing too much wrong," Barty said.
"I gave it a crack and it wasn't enough."
Unseeded after falling to 451st in the rankings during her 16-month maternity leave from the tour, Williams was again commanding the world's attention in her full-body black and red catsuit that she hopes "inspires all mums", especially ones who have also suffered post-pregnancy health issues.
Barty, though, had her own motivations and looked comfortable on centre stage.
Alas, the 22-year-old fell short in her quest to join fellow Australians Samantha Stosur and Daria Gavrilova in the last 32.
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, the 24th seed, 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.
HOW THE AUSSIES FARED AT THE FRENCH OPEN:
Women's singles, second round
17-Ashleigh Barty lost to Serena Williams (USA) 3-6 6-3 6-4
24-Daria Gavrilova bt Bernarda Pera (USA) 5-7 7-5 6-3
Samantha Stosur bt 30-Anastasia Pavlyuchenkova (RUS) 6-2 7-6 (7-1).
