A stunning 2-6 6-3 11-9 victory over Petra Kvitova, the 2011 Wimbledon champion and world No 8, sent the 18-year-old Briton into the third round. More importantly, it confirmed that she now needs to fear nobody in the game.
It was a remarkable match, littered with errors but also full of thunderous shots by two of the sport's biggest hitters. Robson (right) recovered from 3-0 and 4-2 down in a see-saw third set, failed to serve out for the match when she led 6-5, but completed her victory in convincing fashion after breaking the 22-year-old Czech for the last time.
The three-hour contest, played in the main Rod Laver Arena in front of a crowd who were overwhelmingly behind Melbourne-born Robson, finished at 12.30 in the morning. On a day when the temperature peaked at 40C, it was still in the thirties by the time Kvitova failed to return Robson's final serve of the match.
"I never gave up," an exhausted Robson said. "Even when she went up a break twice in the third, I just thought: 'I can always break her serve, I just have to get as many returns in as I can.' And in the end, I just thought: 'I've got nothing to lose, so I'm just going to relax on my serve a bit more and just go for it'."
Kvitova, who has had a poor start to the year, said: "I don't think I've ever served so badly. Laura surprised me with her serve. It took me a while to get used to it because she's a left-hander. She tried to play very fast, the same way that I do. Our games are quite similar."
Robson has to win one more match here to emulate her performance at last year's US Open, when she beat two Grand Slam champions in Kim Clijsters and Li Na to reach the fourth round, but she rated this as her hardest-fought victory.
"I would say all the wins are equally satisfying, but this was probably the toughest in terms of how long the match was and how up and down it was," she said. "I think it's right up there with one of the best wins."
Her reward is a place in the third round against Sloane Stephens, which promises to be a fascinating confrontation between two of the game's most exciting young talents.
Stephens, who is just 10 months older than Robson, is one of a group of emerging young American players. The world No 25, who has been taken under Serena Williams' wing, beat Robson in straight sets in their only meeting at senior level in Hobart last week.
Robson's victory means that two British women have reached the third round of a Grand Slam event for the first time since the 1991 US Open.
Heather Watson was due to play Agnieszka Radwanska in the opening match of today's programme. The performances of the two Britons here should see both of them climb at least 10 places in the world rankings. Watson is currently No 50 and Robson No 53. (© Independent News Service)
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