Flavia Pennetta defeats her compatriot to win US Open title

Flavia Pennetta claimed a first grand slam singles title with a 7-6(4) 6-2 win over Roberta Vinci in an improbable all-Italian US Open final on Saturday to cap an extraordinary fortnight packed with upsets.

Pennetta, 33, becomes the fourth oldest grand slam winner in the Open Era and joins 2010 French Open champion Francesca Schiavone as the only Italian women to win a major title.

The match was set up by jaw-dropping upsets as unseeded Vinci knocked off world number one Serena Williams in the semi-finals to end the 33-year-old American’s quest for a calendar year Grand Slam.

Pennetta's path to the final included two huge hurdles which she cleared with confidence in taking down Czech fifth seed Petra Kvitova in the quarter-finals and Romanian second seed Simona Halep in the semi-finals.

The veteran announced her decision to retire from tennis after the victory, the pinnacle of an almost 20 year career in which she has won ten career WTA singles titles.