Mamma Mia! Pennetta wins US Open, then retires

Flavia Pennetta won her first grand slam singles title over Roberta Vinci in an improbable all-Italian U.S. Open final last night, then added one more shock to a stunning fortnight by announcing her retirement.

With the 7-6(4) 6-2 win, the 33-year-old Pennetta 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 singles title.

But as the celebrations kicked into high gear, Pennetta dropped a bombshell that provided a dramatic finish to the year's final grand slam and her career.

After embracing childhood friend and Fed Cup team mate Vinci at the net a smiling Pennetta stood at center court during the trophy presentation and told a capacity crowd at Arthur Ashe Stadium that included Italian Prime Minister Matteo Renzi that she would retire.

"This is the way I would like to say goodbye to tennis," she said before hoisting the trophy and accepting the $3.3 million winner's check. "I'm really happy. It's what all the players seem to want to do, to go out with this big trophy.

"And so this one was my last match at the U.S. Open and I couldn't think to finish a better...