World number one Iga Swiatek crashed out of the US Open on Wednesday following a defeat against US' Jessica Pegula. The Polish tennis star lost 2-6, 4-6 to sixth-ranked Pegula in quarter-final. "Finally I can say I'm a semi-finalist," said Pegula after the match. She will now face Czech Republic's Karolina Muchova, ranked 52, for a place in the final.