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.