New York, Sept. 4 -- Amanda Anisimova advanced into the final four of the US Open with a remarkable comeback against Iga Swiatek, winning 6-4, 6-3 in a one-hour and 36-minute encounter and overcoming her 6-0, 6-0 defeat in the Wimbledon final earlier this year.

Anisimova's victory sets up a semifinal clash against Naomi Osaka, who defeated Karolina Muchova in straight sets 6-4, 7-6(3).

Anisimova's win marked the biggest upset to date this year, as she took down the No. 2 seed.

When the first set was tied at 4-4, Anisimova had scored 12 winners (and six unforced errors) to Swiatek's seven winners (and six unforced errors).

With Swiatek serving in the following game, the American's continued aggression gained her two set points. The sec...