With a hurricane advancing on Florida and the social fabric of the country intermittently fraying at the edges, Sloane Stephens gave the United States something to smile about here on Saturday, the sort of uplifting story that induces involuntary smiles and tears in tough times, a tale only sport or Hollywood could deliver.

It did not take her long. As destructive wind and rain advanced from the Caribbean on her locked-down home town of Coral Springs, she took just 61 minutes to beat her best friend on the tour, Madison Keys. A New York audience used to drama was at first stunned and disappointed by the lack of a proper fight for their bucks, then drawn to join in the celebration of tennis history.

The score – 6-3, 6-0 – was an embarrassing side story. Keys was hardly in the match from the moment she trembled on serve at the start. She failed to find a rhythm, and the occasion clearly got to her. She stretched the second set to 31 minutes with a lost-cause fightback, saving two match points before a tired final effort dribbled into the net. It was almost a relief to her.

Stephens, who grew up tough and has not always had an easy relationship with celebrity, matured during an 11-month lay-off following last year’s Olympics, and, after consoling her opponent in the immediate aftermath of her finest hour, said courtside, beaming: “I had surgery on 23 January and if someone had told me then I’d win the US Open, I’d say it was absolutely impossible. This journey has been incredible. Maddy’s my best friend on tour. For us to be here is a special moment. I told her I wished it would be a draw. I’m going to support her, no matter what. That’s what real friendship is.”

Stephens, who has blossomed into a charming and intelligent athlete with a smart take on her sport and her social obligations, added: “I should just retire now. I told Maddy I’m never going to be able to top this. Talk about a comeback. I had the right attitude, the best team. Things came together in the last six weeks.”

Back then, incredibly, she was ranked 957 in the world. Since then, she has won 15 of 17 matches. She will be ranked 17 on Monday. That is a startling achievement.

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She and Keys shared injuries, a big stage and no little incredulity. Neither believed earlier in the year that they would be standing together on the last day of the US Open. Her voice trembling, Keys said: “Sloane is truly one of my favourite people. Obviously I didn’t play my best tennis today and was disappointed but, if there was someone I had to lose to, it would be her. I had a really rough start to the year, surgery in the middle of it. If you told me two months ago I would be holding a finalist’s trophy for the US Open I would be really happy and proud of myself.”

Neither had won a slam; neither had been to a slam final. This has happened only seven times in the Open era, and twice here. Into such uncharted territory they wandered, ambitious but wary. What they did know was each other and each other’s tennis, and they shared the support of their home crowd pretty much down the middle, because both brought with them a history of struggle.

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In that regard, Stephens had a marginally better record against Americans, 8-2 to 7-2, and each of them added to that tally in the semi-finals, with Stephens’s finish to eject Venus Williams near to awesome, while Keys embarrassed Coco Vandeweghe to the point of tears for the loss of only three games.

During the fortnight, they proved their pedigree and their commitment. The only guarantee was that there would be a fourth different slam champion in the same year, which last happened in 2014.

Stephens, perhaps unexpectedly against the bigger serve of Keys, struck first, breaking after a quarter of an hour, then held. The nerves seemed to be with the favourite. The expectations on Stephens were, perhaps, not as great, given she had come from nowhere to make the final. She has roared through this championships like a train, her six wins before the final equal to the number she had won in her previous six slam appearances combined.

Her composure got her through as much as the lack of it cost Keys. The winner, not the biggest server, made her inroads off the ground, playing carefully but with a sharp eye for an opening. She hit only 10 winners and not a single ace, but nor did she double fault. Keys found 18 winners, but her endeavour came at a price, with 30 unforced errors to six by Stephens.

The vast majority of the rallies were short, Stephens taking 39 of 55 that lasted no more than four shots. In longer exchanges, Keys got closer to parity, but her strokes were never really convincing. The power and placement that reduced Vandeweghe to a blubbering wreck in the semi-finals, now were drained of all conviction. It was not a pretty sight.

But their hugs and laughter at the end were. These two fine African American athletes brought perspective as well as passion to a final that was more than just another sporting event.