Serena Williams showed she has no intention of ending her singles career without a fight after beating second seed Anett Kontaveit on another remarkable night at the US Open.
Williams, ranked 605th and turning 41 next month, won 7-6 (7-4) 2-6 6-2 to stun the Estonian in New York.
The American recently announced her intention to retire after her home major and is now into the third round.
Williams will play Australia's Ajla Tomljanovic next on Friday.
A few weeks ago, Williams announced she was "evolving away" from playing tennis in an essay for fashion magazine Vogue, but agreed after beating Montenegro's Danka Kovinic on Monday she had been vague about her exact timeline.
While lacking some of the pomp and ceremony from her opening match on Monday, this was another special atmosphere as 23-time major singles champion Williams looked to extend her storied career by at least another round.
After edging a tense opening set, the former long-time world number one suffered a dip of energy from the start of the second set as Kontaveit levelled but she recovered to win an edgy decider.
In the end, Williams handled the occasion better than her 26-year-old opponent - who looked emotional before the final game as she hid under her towel - and secured a victory that left many in an exultant crowd jumping to their feet to celebrate.
