SI Insider: Semifinal Spots Are on the Line at the U.S. Open Today
Today there are two matches on the women's side that will shape the semifinals of this year's U.S. Open. In addition to the semifinal implications, three of the players, Victoria Azarenka, Tsvetana Pironkova, and Serena Williams are mothers. SI senior writer Jon Wertheim shares his thoughts on today's matchups.