Italy’s Roberta Vinci has caused a huge shock as she beat Serena Williams at the US Open to end the American’s hopes of a calendar Grand Slam.

Vinci, the world number 43 and playing her first Grand Slam semi-final, won the American 2-6, 6-4, 6-4 in New York.

While speaking to reporters, she said he beating the world number one is like a dream.

“It’s amazing, like a dream,” she said in her on-court interview.

“I’m in the final. I beat Serena. For me, it’s an amazing moment, incredible, yes.

“For the American people, for Serena, for the Grand Slam, today’s my day. Sorry, guys.”

Meanwhile, Serena had been two wins from completing a clean sweep of all four majors in 2015.

Vinci will play Flavia Pennetta in an all-Italian final at flushing meadows on Saturday.