Serena Williams out, Roger Federer advances at Australian Open
Williams struggled all tournament after injuring her ankle in her opening match. "I'm almost relieved that it's over because there's only so much I felt I could do. I've been thrown a lot of (curve) balls these two weeks," Williams tells the AP.
Stephens now advances to a semifinal against defending champion Victoria Azarenka, which takes place Thursday. The other semifinal in the women's singles bracket will be between Maria Sharapova and Li Na.
On the men's side, Roger Federer pulled out a win over Jo-Wilfried Tsonga in a match that lasted just over 3.5 hours. Federer will face Andy Murray on Friday. The other men's semifinal is between defending champion Novak Djokovic and David Ferrer on Thursday.