Jessica Pegula is one of the players who, depending on results, could take over as world number one after the US Open. However, the world number three had major problems at the start of the quarter-finals.
World number 27 Navarro got Pegula off balance, and after five double faults the 32-year-old slammed her racket to the ground in frustration.
But in the next two sets, it was Pegula's match, and she advanced to the semi-finals after 3-6, 6-4, 6-3.
The match between the Americans was dubbed the "billionaires' fight" in advance, as both Pegula's and Navarro's fathers are successful businessmen.
In the semi-finals, world number one Aryna Sabalenka awaits. However, Pegula can take over the top spot if she wins the entire US Open and world number two Jelena Rybakina fails in the quarter-finals.
