The 19-year-old Andreescu is just the second women’s Grand Slam finalist from Canada -- after Eugenie Bouchard at Wimbledon in 2014 -- and will bid to become the first teen Grand Slam champion since Maria Sharapova won at Flushing Meadows in 2006.
“It’s just surreal. I really don’t know what to say. It’s a dream come true playing Serena in the finals of the US open. It’s crazy, it’s crazy,” Andreescu said.
“I think it’s just all the hard work I’ve put in through the years. If someone told me a year ago I would be in the US Open final this year, I’d tell them they were crazy.”
Andreescu, in her US Open main draw debut, saved a set point in the opening set against fellow first-time Grand Slam semi-finalist Bencic, the 13th seed from Switzerland, before edging the tie-break.
She trailed by a double break at 5-2 in the second set but reeled off the final five games to set up a rematch of last month’s Toronto final against the 37-year-old Williams, who retired from that clash with a back injury.