The 2013 US Open will be the sixth Grand Slam in the Open Era with an Italian semifinalist.
WTA Staff

NEW YORK, NY, USA - With Roberta Vinci and Flavia Pennetta squaring off in the US Open quarterfinals in an all-Italian clash on Wednesday, an Italian is guaranteed to reach a Grand Slam semifinal for just the sixth time of the Open Era. Here are the previous five instances, all of which were achieved by Francesca Schiavone and Sara Errani:

PlayerEventRound Reached
Francesca Schiavone'10 French OpenW
Francesca Schiavone'11 French OpenR-Up
Sara Errani'12 French OpenR-Up
Sara Errani'12 US OpenSF
Sara Errani'13 French OpenSF

Speaking of Italians, this is just the second time in the Open Era that two Italians have advanced to a Grand Slam quarterfinal, with Sara Errani and Vinci having done so at the 2012 US Open.