Bianca Andreescu won her maiden Grand Slam title at the US Open and caused further agony for Serena Williams in her pursuit of an elusive record-equalling 24th major crown.
The 19-year-old Canadian defeated the six-time champion 6-3 7-5 to celebrate a memorable main draw debut at Flushing Meadows as Williams suffered her fourth Grand Slam final defeat since the birth of her first child in September 2017.
Andreescu saw a championship point saved at 5-1 in the second set as Williams fought back but she recovered to become the first Canadian – male or female – to win a Grand Slam singles title.
Both finalists received good backing on their arrival to the Arthur Ashe Stadium for the showpiece but the New York crowd unmistakably reserved the biggest ovation for Williams.
Andreescu, who had spent just shy of three hours more than Williams on court to reach the final, elected to receive first and made the immediate breakthrough as the American conceded her serve with consecutive double faults.
After the Canadian backed up the break, Williams responded with her first hold of serve which was secured with a powerful forehand winner and she followed it by letting out a big scream of encouragement.
Andreescu was not overwhelmed by the occasion or Williams’ natural power from the baseline and brought up five break points in a 10-minute seventh game, only for the former world No 1 to save them all.
But the first-time Grand Slam finalist responded in steely fashion as she served an ace on break point to move within a game of the first set before Williams served a double fault on set point in front of a stunned crowd.
Williams served another double fault – this time on a break point for the third time – as she lost her serve to hand Andreescu the early break in the second set.
A fortunate net cord benefited Williams on the fourth break point of the third game to provide a route back into the final but the eighth seed could not capitalise as she was broken in the next game.
Williams was startled by the performance of Andreescu and quickly fell a double break behind as the match quickly went away from her.
Andreescu brought up a championship point at 5-1 on her serve but Williams saved it with a forehand winner and went on to break for the second time in the match.
From the brink of defeat, Williams maintained the momentum shift as she broke an increasingly tense Andreescu again to get back on serve.
Williams was being roared on by a vocal crowd and regained parity in the set despite serving two double faults in the 10th game but Andreescu halted her four-game run losing run with a battling hold of serve.
The 15th seed, who had lost in the first round of US Open qualifying last year, came into the final without a defeat in a completed match since March 2 and found the willpower to fire a forehand winner on her third championship point to cause a huge Grand Slam shock.