Bianca Andreescu could not have imagined being in the US Open final this time last year but is in no doubt she is worthy of her place across the net from Serena Williams on Saturday.

Making her first appearance in the main draw at Flushing Meadows, the 19-year-old Canadian progressed to the final with a hard-fought 7-6 (7-3) 7-5 win over Belinda Bencic in Thursday's semi-final.

It is a scenario that would have been hard to envision 12 months ago when Andreescu lost in the first round of qualifying in New York.

However, Andreescu came through the preliminaries to reach the final in Auckland at the start of 2019, beating Caroline Wozniacki and Venus Williams along the way, and made a huge breakthrough at Indian Wells in March with victory over Angelique Kerber in the final.

Andreescu pinpointed those tournaments as the events that gave her the belief she could contend for major titles, but still conceded to struggling to comprehend what she has achieved this year.

Speaking at a media conference, Andreescu was asked what she would have said a year ago if someone told her she would be facing Williams on this stage.

She replied: "I don't think I would have believed them. I was ranked, like, outside of the 150, I think. It's just crazy what a year can do.

"If someone would have said that a couple weeks ago, I think I would have believed them.

"I've always dreamt of this moment ever since I was a little kid. But I don't think many people would have actually thought that it would become a reality.

"It all started in Auckland, then in Indian Wells. I just kept believing in myself."

Andreescu put her hands on her head after clinching victory over Bencic and added: "I think that moment after the match, I was just in shock.

"At the same time, I fought really hard to get to this point, so I really think I deserve to be in the finals on Saturday."

The teenager played four games with Williams in the Rogers Cup final last month before the American retired from the match.

She said of the prospect of facing the 23-time grand slam singles champion: "I remember always telling my team I would have always wanted to play her right before she retires.

"I'm really looking forward to it. She's an amazing champion on and off the court. It's going to be fun.

"She's fighting for her 24th on Saturday. I'm sure she's going to bring her A game. I'm going to try to bring my A game, too."

Andreescu dealt with a hostile crowd in her fourth-round match with American Taylor Townsend and appreciates she will have even less support against Williams, who is looking to tie Margaret Court's grand slam singles record.

"I don't know how that's going to go. But hopefully I can have some Canadians cheering me on," said Andreescu. "I remember I heard some during Taylor's match. For sure, the crowd's going to be for Serena. I just have to deal with that."