Getty Images Sloane Stephens, Madison Keys

Two American women will player for the U.S. Open title Saturday afternoon. No, they are not Serena Williams and Venus Williams. And no, neither is Chris Evert, Martina Navratilova, Billie Jean King, Monica Seles, Jennifer Capriati, Lindsay Davenport or any other name the ultra-casual fan might recognize.

Sloane Stephens, 24, and Madison Keys, 22, are both playing in their first Grand Slam final. But for tennis diehards, they've been a fixture in the women's game for a while now. They've also known each other going back to their tween years.

One of them will become the first American Grand Slam women's champion not named Williams since Capriati in 2002 and the first to do so at the U.S. Open since Davenport in 1998.

Where'd They Come From?

Stephens: She comes from a family of stud athletes. Stephens' mother, Sybil Smith, was a standout swimmer at Boston University, who became the first African-American female to be a first-team All-American in Division I swimming history.

Stephens' father, John, was the 17th pick in the 1988 NFL Draft after starring at Northwestern State. He played six seasons at running back for the Patriots, Packers, Falcons and Chiefs. His best season was 1988 when John rushed for 1,168 yards and four touchdowns, earning NFL Offensive Rookie of the Year honors and a Pro Bowl selection. However, Sloane can only remember meeting her father two or three times in person. He died in 2009 when she was 16.

Stephens was born in South Florida, but she spent some of her early childhood in Fresno, California. When she started to get serious about tennis, Stephens moved to Boca Raton at age 11 to go to the Evert Tennis Academy and then attended the Nick Saviano High Performance Tennis Academy in Plantation, Florida.

Keys: She was born in Rock Island, Illinois, and no, that's not a Chicago suburb. Rock Island is one of the "Quad Cities," on the Illinois-Iowa border, along with Moline, East Moline, Bettendorf and Davenport (yeah, that's five cities, don't ask). Keys is one of four siblings born to attorneys Rick and Christine.

Keys left home at age 9 to go to the Chris Evert Academy (around the same time as Stephens) and turned pro on her 14th birthday in 2009.

Early Competitive Years:

Stephens: As a junior, Stephens showed more promise in doubles than singles. She made four junior doubles finals, winning three with partner Tímea Babos (2010 French Open, 2010 Wimbledon and 2010 U.S. Open). Stephens was given three attempts at qualifying for the main U.S. Open draw from 2008-2010, but failed on all three tries. After finally turning pro, she made her U.S. Open debut in 2011, reaching the third round.

Keys: Jumping over juniors, Keys made her presence known immediately. In her first pro match in 2009, she beat then-world No. 81 Alla Kudryavtseva. That July, at a World TeamTennis event, Keys, at 14, beat Serena Williams, 5-1. In 2011, as a 16-year-old, Keys made her U.S. Open debut by defeating veteran American Jill Craybas. She took world No. 27 Lucie Safarova to three sets in Round 2, but lost.

Sloane Stephens

Breakout:

Stephens: Stephens began making her move in 2012. She won at least one match at every Grand Slam, going as far as the fourth round of the French Open. In one year, she jumped all the way from No. 97 in the world to No. 38. Then at the 2013 Australian Open, as the No. 29 seed, Stephens blasted her way to the semifinals. However, it was the quarterfinals that put Stephens on the map, when she upset Serena Williams, the No. 3 seed. Stephens came from one set down to beat her childhood idol and be the last American at the event. Stephens proceeded to go to the fourth round in Paris, quarterfinals in London and fourth round in NYC. Stephens would reach her career peak of No. 11 in the world that year.

Keys: Keys had her breakout in Melbourne at 19 in 2015. Unseeded, she reached the semifinals and upset Venus in the quarterfinals in three sets. Serena then beat Keys in straight sets in the semifinals. Keys backed up that performance with a trip to the quarterfinals at Wimbledon later that year. Keys rode that momentum into a successful 2016, where she made three WTA finals, winning one. She eventually reached a career-high ranking of No. 7 last October.

Injuries

Stephens: After her big 2013, Stephens hung around the world top 40 for the next three years. She won her first four WTA titles from August 2015-April 2016, but last August, Stephens ended her season early with a right foot stress fracture. She subsequently had foot surgery in January, sidelining her for half of 2017.

Stephens returned at Wimbledon, where she lost in the first round. She again lost in the first round at her next tournament, the Citi Open. Just one month ago, Stephens was technically No. 957 in the world. Two semifinals runs at the Canadian Open and Cincinnati Masters quickly propelled Stephens back into the top 100 in the world, but she still earned her ticket to this year's U.S. Open with a protected ranking. Stephens entered ranked No. 83, but she is likely to be in the top 30 when the next batch of rankings comes out.

Keys: Likewise, Keys' hot streak stalled with an injury. Although she entered this year at No. 8 in the world, Keys missed the season's first two months -- and the Australian Open-- with a wrist injury. Keys returned with a run to the Round of 16 at Indian Wells, but she struggled mid-season. At one point, she went through a 2-6 stretch and her ranking dropped to No. 21. Keys did manage to come into the U.S. Open on a 6-1 run, which suggests her No. 15 season may have been flawed.

Madison Keys

Pro Comparisons

Stephens: Justine Henin. Americans have been spoiled with hard hitters in the Wiliams Sisters Era. Although Stephens is imposing with a muscular build, she relies on hitting clean strokes and placement. Stephens actually won her quarterfinal over Anastasija Sevastova without recording an ace in three sets. At 5-7 Stephens has to rely on her consistency and a bit of pushing. In her semifinal versus Venus, the elder Williams sister had 28 winners and 51 unforced errors. Stephens had 17 winners and just 27 unforced errors. However, Williams had to cover more distance -- 7,619.3 feet versus Stephens' 7,209.9 feet -- showing how much Stephens' placement matters.

Keys: Venus Williams. If Williams' game couldn't get past Stephens on Thursday, Keys will just have to put together a better version. Keys is 5-10 and uses her long wingspan to play a much more up-and-down style of play. She'll take forehand winners high and use her serve as a weapon. Keys had 13 combined aces in her two two-set wins in the quarterfinals and semifinals. She won't shock anyone with speed, but Keys' reach makes up for that.

Demeanor

Stephens: All business. Stephens is not on tour to make friends. She idolized Serena growing up, but after beating her in Melbourne in 2013, she joked about putting up a photo of herself on her wall. Williams would respond with a tweet simply saying, "I made you." Stephens has all been quoted as saying the Williams Sisters spurned her attempt at an autograph during her youth. So many players have stared down the Williams Sisters and failed, but Stephens proved again this tournament she is not afraid of the bright lights.

Keys: Keys is still growing up. During her early rise to prominence, she could play off the free-spirit teenage persona. After all, she never had a real high school life. But now 22, Keys is turning into an adult before the tennis media's eyes. It definitely helps that she is on her second stint with Lindsay Davenport as her head coach. Davenport was one of tennis' fiercest competitors over a decade ago and she knows a thing or two about overcoming the Williams Sisters. 

Keys is perhaps the current American star most conscious of her social reach. As a mixed-race woman with a Heartland spirit, she is an easy draw to a vast array of children.

Bottom Line:

Stephens: Many critics thought the ship had sailed on Stephens already. She showed promise earlier and seemed like she might fall back to a middle-of-the-road player. What started as a nice return from injury turned into an opportunity for a career-changing title as the past two weeks went by. Stephens has been playing without pressure and she needs to take that looseness into the final. If she can keep swinging freely, there is no reason Stephens can't finish this hot stretch and subsequently return to the top of the sport's rankings. Stephens won their only matchup, a two-set affair in Miami in 2015.

Keys: There is much more pressure on Keys. She is the higher ranked player, and she is the woman American tennis fans have turned to, at least in the [ast 24 months, to be the Williams Sisters' chief replacement. She has Davenport in her corner and will likely have the crowd Saturday. Unlike Stephens, Keys has looked shaky at points this tournament, but she has perhaps played her two best matches coming into this final. At the end of the day, Keys has more room for error than Stephens and is the favorite, but that's why you play the match.

-- Follow Jeff Eisenband on Twitter @JeffEisenband. Like Jeff Eisenband on Facebook.

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