Threatening to shove a tennis ball down a line judge's throat can't be topped, but Serena Williams did have an outstanding meltdown during her Australian Open quarterfinal loss to Sloane Stephens last night. You Don't Want To Be Behind This Guy

So exactly who is this 19-year-old young tennis whiz kid Sloane Stephens (pictured)? Do we know much about the young dynamo who beat Serena Williams (both pictured below), the best American women's tennis player to ever swing a racket, during day 10

MELBOURNE, Australia — It took 137 minutes for someday to arrive for Sloane Stephens. [+] Enlarge Sloane Stephens AP Photo/Dita Alangkara Even Sloane Stephens seemed a bit shocked after she pulled off the upset of third-seeded Serena Williams.

The nineteen-year-old pro athlete tops this week's current events roundup.

Victoria Azarenka of Belarus walks off the court to take a medical time out during her semifinal match against Sloane Stephens of the US at the Australian Open tennis championship in Melbourne, Australia, Thursday, Jan. 24, 2013. (AP Photo/Dita