(Reuters) - Following is a list of biggest shocks in women's tennis after Italian outsider Roberta Vinci, ranked 43rd, beat world number one Serena Williams in the U.S. Open semi-finals to deny the American a chance to complete a calendar year Grand Slam.
1: Roberta Vinci beats Serena Williams 2-6 6-4 6-4 in the Flushing Meadows semi-finals to halt the American's 33-match winning streak at the majors. Before arriving in New York in 2015, the 32-year-old Italian's best grand slam performance was two quarter-final appearances in 43 attempts. Despite the odds stacked against her, doubles specialist Vinci condemned 21-times major singles champion Williams to her first defeat at a grand slam since Wimbledon in 2014.