NEW YORK, NY, USA - The identity of the final two semifinalists at the US Open will be confirmed on Wednesday as Roberta Vinci locks horns with Fed Cup teammate Flavia Pennetta and last year's runner-up Victoria Azarenka takes on Daniela Hantuchova.
Arthur Ashe Stadium
 Roberta Vinci (ITA #13) vs. Flavia Pennetta (ITA #83)
Head-to-head: series tied 4-4
In January 2003, two fresh-faced Italian prospects met in the first round of an ITF Circuit event in Ortisei. A decade later, Roberta Vinci and Flavia Pennetta will meet once again, this time with a place in the last four of the US Open on the line.
Pennetta has lost her three previous quarterfinals in New York, but this fortnight has been performing with the carefree confidence of a player unconcerned with past records. Along with Serena Williams, she is one of two players yet to drop a set and exhibited an impressive display of aggression - and concentration - to defeat the in-form Simona Halep in their rain-interrupted fourth round.
Unlike Pennetta, whose past few years on tour have been blighted by a serious wrist injury, life after 30 appears to be suiting Vinci rather well; this year has brought two titles and she is now just one win away from a Top 10 debut. These accomplishments leave her as the slight favorite, although Pennetta's more aggressive game and current form leaves the outcome intriguingly up in the air.
 Victoria Azarenka (BLR #2) vs. Daniela Hantuchova (SVK #48)
Head-to-head: series tied 2-2
With just two wins in her past six tournaments and first round exits at her past five majors, Daniela Hantuchova was not many people's choice to be the one left standing from a section of the draw that also contained Petra Kvitova and Samantha Stosur.
However, the Slovak has survived a few hairy moments - including four match points against Julia Glushko in the third round - to reach her first Grand Slam quarterfinal since 2008. Her opponent there, Victoria Azarenka, has had a similarly taxing route, going the distance in her past two matches.
In the second of these, against Ana Ivanovic, Azarenka was forced to draw on all her reserves of mental fortitude to withstand a blizzard of early winners before gradually turning the encounter around to improve her record on hard this year to 29-1. Like Ivanovic, Hantuchova has the capability to breach Azarenka's defenses from the baseline and she will need to adopt a similarly positive gameplan from the outset if she is to stand a chance of springing an upset.