Venus Williams search for her first US Open final since 2002 was cut short by Sloane Stephens, who defeated the seven time Grand Slam champion 6-1, 0-6, 7-5.
Stephens had missed 11 months with a left foot injury displayed great determination and fight to overcome Williams in a classic US Open encounter.
Stephens, whose best prior Slam run was to the 2013 Australian Open semi-finals will face US compatriots Madison in an all American final for a top prize of $3.7 million.
It has been an incredible road to finals for Stephens, was ranked 957th in July after a long layoff due to injury, but since then she has won 14 of her past 16 matches, now 83rd, Stephens is the lowest ranked Slam finalist since unranked Justine Henin at the 2010 Australian Open.
It's the first all-American US Open women's semi-finals since 1981 and the first at any Slam since Wimbledon in 1985. Saturday will be the first all-American US Open women's final since Serena Williams beat Venus in 2002.
While 37-year-old two-time champion will end 2017 without another major title despite reaching two finals and a semi-final.