Sloane Stephens wins the US Open

Sloane Stephens of the US kisses her winning trophy after defeating compatriot Madison Keys in their 2017 US Open Women's Singles final match at the USTA Billie Jean King National Tennis Center in New York on September 9, 2017. Sloane Stephens, sidelined for 11 months by a left foot injury until returning in July, captured her first Grand Slam title by routing fellow American Madison Keys 6-3, 6-0 in Saturday's US Open final. / AFP PHOTO / DON EMMERT (Photo credit should read DON EMMERT/AFP/Getty Images)

Sloane Stephens’ epic comeback is complete.

Stephens, who has jumped more than 900 spots in the world rankings in a month, is now a grand slam champion, winning the US Open 6-3, 6-0 against No. 15 seed and fellow American Madison Keys at Arthur Ashe Stadium in Flushing, New York.

This was only the seventh time in the Open Era, and the second time at the US Open, that two first-time finalists have faced off in a grand slam final. This also was the first all-American US Open final since 2002, when Serena Williams defeated Venus Williams.

The 24-year-old Stephens, unseeded and ranked 83rd, is the third player to win the US Open ranked outside the top 10 since computer rankings began in November 1975. The others were unranked Kim Clijsters in 2009 and No. 26 Flavia Pennetta in 2015.

None of this looked possible earlier this summer.

Stephens, who had been sidelined for 11 months after a foot injury and underwent surgery in January, made her comeback at Wimbledon and entered this summer’s US Open Series ranked 957th. But she’s been on a tear in the North American events, reaching the semifinals in Toronto and Cincinnati.

With the win, Stephens is projected to rise to No. 17. She also nets a hefty payday: $3.7 million. Her career earnings heading into this tournament were $4,519,709, with $310,546 coming this year.

Keys, 22, is projected to move up to No. 12 by reaching the final.

An improbable run

Stephens, who started playing tennis at age 9, comes from an athletic family. Her mother, Sybil Smith, is a former collegiate swimmer at Boston University. Her late father, John Stephens, was an NFL running back in the late 1980s and early 1990s.

Stephens made her breakthrough in 2013 when she defeated Serena Williams to reach the Australian Open semifinal. She would go on to lose to eventual champion Victoria Azarenka.

Her first singles title was in 2015 in Washington. She added three more titles in 2016.

The potential has been there for her to win a grand slam, but what she’s done this summer, considering the circumstances with her previous injury, is shocking.

Heading into Saturday’s final, Stephens had won 14 of her last 16 matches, including defeating No. 9 Venus Williams in the semifinal. She’s one of three players who have never held the No. 1 ranking who have beaten both Williams sisters in grand slam events.

Stephens now has more wins at the year’s US Open matches (seven) than she had in her last six grand slam appearances combined (six).

Stephens didn’t play in the US Open last year because of the foot injury.

Unranked players aside, Stephens is the second-lowest ranked player to reach and win the title match at a grand slam, after No. 111 Chris O’Neil, who won the 1978 Australian Open. She’s the lowest ranked player to reach and win the title match at the US Open.

Stephens is the fourth unseeded player to reach the final in the US Open and 14th in grand slam finals in the Open Era.

Excluding when unranked Clijsters won in 2009, the matchup between No. 16 Keys and No. 83 Stephens, with a combined ranking of 99, is the lowest title match at the US Open since computerized rankings began in November 1975.

In addition to Stephens, Keys also was making a comeback from injury.

For Keys, this year’s US Open was just her 10th tournament of 2017. During the off-season, Keys underwent surgery on her left wrist and missed the first two months of the year. She also, according to the WTA’s website, had a second surgery on the wrist ahead of Wimbledon, and she also withdrew from Rogers Cup in Toronto because of a left forearm injury.

The No. 15 seed has never won the US Open. The last time a 15 seed won a major was Marion Bartoli at Wimbledon in 2013.

Youth movement

With this result, four different players won this year’s majors — the first time that’s happened since 2014. Serena Williams won the Australian Open, Jelena Ostapenko was the French Open champion, and Garbine Muguruza hoisted the Wimbledon trophy. It’s the 12th time that has happened in the Open Era.

There are also signs of a changing of the guard in women’s tennis. Ostapenko, 20, became the first unseeded player and lowest ranked player to win Roland Garros in the Open Era. Muguruza, 23, became the only player to defeat both Williams sisters in a grand slam final when she defeated Venus Williams to win Wimbledon. When the rankings are released Monday, Muguruza will be in the top spot for the first time.

Stephens joins Muguruza, Ostapenko and Petra Kvitova as players born in the 1990s to win a grand slam title.

This year’s US Open was the third final in the past five grand slam events not involving a player age 30 or older.

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