The Briton will be confirmed in the world’s top 50 if she beats American Peyton Stearns, who edged her out in an epic battle in Austin in February.
“It has been a massive goal of mine to be inside top 50,” said Boulter, who stands at No50 in the live rankings, but who could yet drop a couple of places depending on other results in New York.
“I’ve always believed I could be there. I know a lot of people put a lot of emphasis on 100, but for me 50 was always a number that I wanted to reach. I think that’s a really good springboard to push and have a go at these girls.
“When you start getting in the main draw of these events and you don’t have to qualify every week, it really helps, physically as well. You have a free swing each week. It’s a number I want to get to, but I’m not there yet and I want to build that and get it higher and higher.”
On Thursday, Boulter battled past Chinese qualifier Yafan Wang 5-7, 6-1, 6-4, overcoming a nasty moment when she could have been defaulted had a ball which she flicked towards the back fence hit a spectator instead of landing in an empty part of the stands where a cameraman was stationed.
Boulter said it would have been her “worst nightmare” had that happened, but though she was warned for ball abuse, she bounced back well to set up a clash with Stearns.
Jodie Burrage, meanwhile, lost in the second round to No2 seed Aryna Sabalenka but will climb to a new career-high ranking of world No85.