The Belarusian, who was tipped up pre-tournament by Sporting Life's Andy Schooler, suffered one of her darkest days when she lost last year’s final to Coco Gauff.
She threatened a repeat of that wobble with some nervy moments, but this was her time, beating Jessica Pegula 7-5 7-5.
It is her second grand slam title of the year, following victory in Australia, and third in total as she proved herself to be the best hard-court player in the world, with few able to match her power in these conditions.
Defeat broke the heart of Pegula, who dreamed of winning a maiden grand slam title in front of an American crowd in the New York state she was born.
She had strong support on Arthur Ashe but was unable to tame Sabalenka’s power despite serving for the second set.
Still, it was a fine tournament for the 30-year-old, whose tycoon father owns NFL side Buffalo Bills, and she continues to knock on the door on the biggest stage.
It looked like Sabalenka was in for an easy evening when she won four out of five games to serve for the first set at 5-3. But then it all started getting a bit complicated and her capitulation in last year’s final must have come into her head.
Pegula rallied to level at 5-5 and had a break point to go in front, but Sabalenka dug herself out of a hole. She then put the American’s serve under pressure and eventually broke to take the first set at the fifth attempt.
That appeared to ease the pressure and Sabalenka raced into a 3-0 lead in the second set, with glory seemingly in touching distance.
But another wobble came as Pegula rattled off five successive games, which allowed herself to serve to level at one set apiece.
Sabalenka must have been having palpitations at the thought of history repeating itself but she intervened.
A crunch break at 5-4 saved her from going into a decider before an even bigger hold to move a game away.
Suddenly Pegula was serving to stay in the match, but the Belarusian was on a mission and claimed a straight-sets victory.
Sabalenka speechless
Sabalenka said: “I am speechless right now. So many times I thought I was so close to getting the US Open title, it has always been a dream of mine and finally I have got this beautiful trophy, it means a lot.
“I remember all those tough losses in the past here. Never give up on your dream and keep trying and working hard.
“If you sacrifice everything for a dream you are going to get it one day. I am super proud of myself.”
Pegula said: “It has been an incredible time, to be standing here in my first grand slam final, I didn’t expect it.
“I am really grateful for the last few weeks of tennis and some incredible matches I have been able to put together.
“I wish she would have at least let me get one set. We had a tough match a few weeks ago, she is the best hard court player in the world so I knew it was going to be tough.”
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