Photos: Rising tennis star Sloane Stephens

American teenager Sloane Stephens stunned Serena Williams on Wednesday, January 23, beating the 15-time grand slam winner 3-6, 7-5, 6-4 to reach the Australian Open semifinals. It was an unlikely victory for the 19-year-old tennis pro.

American teenager Sloane Stephens stunned Serena Williams on Wednesday, January 23, beating the 15-time grand slam winner 3-6, 7-5, 6-4 to reach the Australian Open semifinals. It was an unlikely victory for the 19-year-old tennis pro.