DHAKA: Serena Williams's hopes of securing a calendar Grand Slam were ended in stunning fashion by Italy's Roberta Vinci in the US Open semi-finals.

Vinci, the world number 43 and playing her first Grand Slam semi-final, caused a huge upset with a 2-6 6-4 6-4 win.

Williams, 33, had been two wins from completing a clean sweep of all four majors in 2015, reports BBC.

Vinci, 32, will play Flavia Pennetta in an all-Italian final at Flushing Meadows on Saturday.

Pennetta, the 26th seed, outplayed Romanian second seed Simona Halep in the first semi-final to win 6-1 6-3.

Saturday will see the first Grand Slam final between two Italian players since the Open era began in 1968.

Williams's hopes of winning a first calendar Slam ended just two victories short, and in the most sensational of upsets.

The American had survived 11 final sets in Grand Slam matches during 2015, but at the 12th time of asking came up against an opponent who simply grew stronger.

When Williams smashed her racquet after dropping the second set it was clear that the tension was beginning to boil over, and her cries of "come on" in the third set took on an increasingly desperate air.

BDST: 0936 HRS, SEP 12, 2015
RS