Roberta Vinci of Italy hits a return to Flavia Pennetta of Italy during the women’s final on the thirteenth day of the 2015 US Open Tennis Championship at the USTA National Tennis Center in Flushing Meadows, New York, USA, 12 September 2015. The US Open runs through 13 September, which is a return to a 14-day schedule. EPA/JASON SZENE

Flavia Pennetta of Italy hits a return to Roberta Vinci of Italy during the women’s final on the thirteenth day of the 2015 US Open Tennis Championship at the USTA National Tennis Center in Flushing Meadows, New York, USA, 12 September 2015. The US Open runs through 13 September, which is a return to a 14-day schedule. EPA/JOHN G. MABANGLO

Flavia Pennetta of Italy (R) embraces Roberta Vinci of Italy at the net after the women’s final on the thirteenth day of the 2015 US Open Tennis Championship at the USTA National Tennis Center in Flushing Meadows, New York, USA, 12 September 2015. The US Open runs through 13 September, which is a return to a 14-day schedule. EPA/JASON SZENES

Roberta Vinci of Italy holds the runner-up trophy after losing to Flavia Pennetta of Italy in the women’s final on the thirteenth day of the 2015 US Open Tennis Championship at the USTA National Tennis Center in Flushing Meadows, New York, USA, 12 September 2015. The US Open runs through 13 September, which is a return to a 14-day schedule. EPA/DANIEL MURPHY

Flavia Pennetta of Italy celebrates with the championship trophy after defeating Roberta Vinci of Italy in the women’s final on the thirteenth day of the 2015 US Open Tennis Championship at the USTA National Tennis Center in Flushing Meadows, New York, USA, 12 September 2015. The US Open runs through 13 September, which is a return to a 14-day schedule. EPA/JUSTIN LANE