Sloane Stephens couldn't walk. Just seven months ago, if someone told Stephens that she was destined to win the US Open in September, she probably would've laughed them out of the room. But on Saturday afternoon, she completed one of the most surprising runs in recent Grand Slam tennis, thoroughly dominating her final opponent to take home the first Grand Slam title of her career. After a most improbable year, she can now recognize one of her greatest lifetime triumphs.

The newest US Open champion

Nobody thought Saturday's championship would be a walk in the park for Stephens. She was the unranked opponent, while Madison Keys was the 15-seed in the tournament.

They were both coming off victories over fellow Americans in the US Open semifinals; Stephens looked decent while upsetting Venus Williams in a roller coaster match, while Keys looked cleaner in a victory over Coco Vandeweghe.

But it turned out to be a breeze for the 24-year old. She won the first set 6-3, then totally dominated the second set 6-0, becoming just the second person to clinch the US Open without dropping a game in the final set. It was such a dominant performance that the highlights largely came after the match, when Stephens shared a very touching embrace with Keys, made her way through the stands to greet her biggest fans, and broke out the world's best facial expression when she learned just how much prize money she earned for her victory.

Stephens on top

A few years ago, Stephens seemed like the next big thing in American tennis.

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She reached the semifinal of the 2013 Australian Open, defeating Serena Williams to make it to that stage. She was on the rise, destined to take the mantle from the Williams sisters and become a constant threat at the US Open and Grand Slam tournaments across the calendar. Then, inconsistencies and questions about her interest in tennis began to dominate the story.

Her latest setback came last August when she had to pull out of the US Open with a foot injury, which required surgery in January. She didn't even begin her comeback until Wimbledon a couple of months ago. Yet she looked to be in rare form this fortnight, becoming the first American without the Williams name to win the US Open since 1998, when Lindsay Davenport was victorious. It's too soon to say if this means Stephens is ready to assume her mantle atop the women's game, but it's definitely her biggest step in the right direction.