Sloane Stephens: The Teenage Star Who Beat Serena Williams

"@sloanetweets congrats on a great match. Excellent focus n poise. Keep it goin. When u defeat a legend you become a legend. Keep it going," Shaquille O'Neal tweeted.

"Wow. What a win for Sloane. Some amazing defense. She gets every ball back," Dallas Mavericks player Dirk Nowitzki tweeted.

The real test now is to see how Stephens can handle the pressure of the main stage of tennis and if she can keep rising.

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"Could Sloane put back-to-back matches together? How's she going to react?" Brennan wondered. "There are a lot of unknowns. Sloane is now going to enter a new phase of her career."

Stephens' mother said her daughter has a good head on her shoulders. She's determined to play her game the best that she can but she also schedules valuable time with friends and family.

"She called home last night right after the match. She was getting ready to go into press, and she goes, 'What are you guys doing?'" Smith said. "It was three minutes of what's going on at home right now. It wasn't even about tennis."