Playing in her first-ever US Open main draw and only her fourth Grand Slam main draw ever, the No. 15-ranked Canadian came back from a set down to overcome Elise Mertens of Belgium, 3-6, 6-2, 6-3. The 19-year-old's breakthrough season includes her first career WTA titles at Indian Wells and Toronto.
She saved a set point at 5-6 and two more in the tie-break, but a long forehand gave Bencic the upper hand.
Andreescu will face 23-time Slam champion Serena Williams for the championship on Saturday. The win put her in elite company, joining Chris Evert, Pam Shriver and Venus Williams as the only women to make the final four on debut in NY.
With 18 years between them, the pair will have the largest age gap of any women's finalists at a major in the Open Era.
"It would be really nice if the boys could also make it to semifinals", she said, "but I'm happy I can kind of do it for them and don't let them down". Their exchange in the final earned the Canadian a legion of new fans as she consoled the veteran with encouraging words and hugged her.
When Andreescu broke Mertens to go ahead 5-3 in the waning moments of the third set, following her 38th victor that was produced by a solid backhand return, it was a matter of time before it would be lights out - game, set and match.
"If you had told me a year ago that I would be in the semifinal of the U.S. Open, I would have said you were insane", Andreescu said in her post-match news conference. Her win-loss tally, following her run in NY, now stands at 43-4 - numbers which were once matched only by the likes of Serena Williams and other prominent giants. "I tried to play a little bit smarter". Of course, I think you can see it there.
"If it happens, then I think I can pave way for many other athletes, the next generation", Andreescu said, "not only for Canadian tennis, but I think for many people".
The teen has a 7-0 record against the WTA's Top 10 this year and her win-loss record for 2019 is the highest winning percentage of anyone on tour. Soon, Andreescu closed out the two hour and two minute match with a backhand victor that whizzed past the dejected Mertens.
Clijsters was indeed one of the idols who inspired Andreescu's style of play.
"I just told myself to stay calm and stick to the tactics", she said when asked what she told herself after falling behind.
'It's definitely not going to be easy, ' added Andreescu. Bianca Andreescu, Canadian-born to Romanian parents who fled their country to seek a better life during the dictatorship of Nicolae Ceausescu, is undeniably confident, and she plays with an evident swagger, bashing shots all over the court and punctuating the big points with enthusiastic hollers.