• British teenager beat Leylah Fernandez 6-4, 6-3 in final
• ‘I’m still only 18 years old. I’m just having a free swing’

Emma Raducanu has vowed to keep her free-swinging and carefree approach to tennis after pulling off one of the great sporting feats with victory at the US Open – just the British 18-year-old’s second ever major tournament, in which she won 10 matches after coming through qualifying, all of them in straight sets.

Related: Emma Raducanu: British 18-year-old makes tennis history with US Open final win

• 18-year-old Briton beats Leylah Fernandez 6-4, 6-3
• Victor came through qualifying and did not lose a set

There are so many basic milestones that Emma Raducanu has not yet recorded in a professional tennis career that only began in full three months ago. She has never been a direct entrant to a grand slam main draw, she is yet to play a tour-level three set match and she has not even won a match at a WTA tour event.

Yet sometimes a special player comes along and renders convention irrelevant. After three weeks and one of the most astonishing breakout runs in living memory, Raducanu marked herself as a grand slam champion for ever. She ended the US Open where she started it: fearlessly dominating from inside the baseline as she defeated Leylah Annie Fernandez 6-4, 6-3 in a match of the highest intensity to win the title without dropping a set.

• As it happened: Bryan Graham’s game-by-game report
• Teenager is first British female grand slam finalist since 1977
• Briton also first qualifier to reach major final in Open era
• Canadian beats No 2 seed Aryna Sabalenka 7-6, 4-6, 6-4

When Emma Raducanu arrived at Flushing Meadows this year, she did not have the faintest idea of where to go. So unfamiliar was she with her surroundings, she needed help from her fellow players just to navigate the tournament’s vast grounds.

Her growth over the past three weeks since those timid first steps has been astounding as she outplayed everyone put in front of her. And under the lights of the Arthur Ashe Stadium on Thursday night she went even further, producing yet another brilliant performance to reach her first grand slam final.