Madison Keys is ranked in the top 10 in the world, a Grand Slam semifinalist who just played for an Olympic bronze medal and has earned career prize money of well over $4 million.

She's also only 21, much closer in age to her middle school days than to No. 1 Serena Williams, and the youngest woman in the top 20 by nearly a year-and-a-half.

This is where the American finds herself as she heads into next week's U.S. Open: an established pro with the game to win major titles, yet competing in a sport in which many players now peak in their late 20s and even early 30s.

Patient and impatient at the same time about her tennis, Keys is also sorting out what she wants to accomplish off the court. She announced Wednesday that she will fund and host six summits for teens at schools around the world in 2017 in partnership with the organization FearlesslyGIRL.

''That's such a tough time for any girl - I know it was a tough time for me,'' Keys said in a recent phone interview.

''To sit down in a big group and talk to each other about it, you realize you're not so alone,'' she added. ''It makes everything seem so much smaller and more manageable.''

Keys has two younger sisters and sees this in a way as just adding many more.

''It's being able to relate to them on such a personal level,'' she said, ''but also knowing it does get better.''

For her, sports was always a part of that.

''When you're 13 or 14, sometimes you wake up in a bad place,'' she said. ''You feel like everything's out of your control. You don't know what to do.

''The second I was on the tennis court, I had the structure I wanted. I was in complete control of what I was doing.''

Long considered one of the world's most promising young players, Keys burst through to the semifinals of the 2015 Australian Open while still a teenager.

''All of a sudden, people say, `She's a contender,''' Keys recalled. ''It's the next logical step: You made the semifinals, you should make a final. You make a final, you should win.

''Unfortunately, that's not how it works.''

The rest of the year, she lost in her first or second match of a tournament nine times, though her results in the Grand Slams were better. And with her profile soaring, so did the harassment on social media.

''I could go through my Twitter account right now and there would be 10 horrible messages,'' Keys said.

''All of a sudden,'' she recalled, ''I was getting all these messages that I was fat and ugly, and I wasn't prepared for it.''

It took time for her to remind herself that the trolls were most likely gamblers who spewed vitriol because they were betting on a match. That realization was crucial.

''If you're not in my immediate circle,'' she said, ''you're not someone whose opinion I value.''

On the court, she needed to remind herself to trust the process and not obsess over individual wins and losses. In 2016, the upward trajectory has resumed. Keys has made three finals, winning her second WTA title, and is currently ranked a career-best ninth. At the Rio Games, she made it to the semifinals - then ran into two Grand Slam champions in a row in Angelique Kerber and Petra Kvitova, losing to both to miss out on a medal as their superiority showed.

Keys, who withdrew from this week's Connecticut Open with a neck injury, is set to be seeded eighth when the U.S. Open starts Monday - a key number because it means she can't meet Williams or Kerber until the quarterfinals at the earliest. She's been eliminated in the round of 16 at her last four majors.

''We believe she'll win a Grand Slam really soon,'' said her agent at IMG, Max Eisenbud, who has also managed Maria Sharapova and Li Na.

At a time when seven of the top 20 players in the women's rankings are in their 30s, the younger generation has finally started to push through in recent months. Garbine Muguruza, 22, won the French Open, then Monica Puig, also 22, was the surprise Olympic gold medalist.

''I want to get to that next step as quickly as I can,'' Keys said. ''If that's three weeks, great. But if it's three months, no problem, or even three years.''