The steep-serving 22-year-old from Prague, who last month became the youngest player in the current top 20, battled past Garbine Muguruza with a nerve-shredding 6-4 5-7 7-5 victory.
The elegantly gifted 21-year-old Muguruza, from Barcelona, possessed the more supple and flexible game, giving her more options in a tricky wind, but it was Pliskova who snatched a memorable win just as her chances seemed to be fading.
Pliskova fired down 13 aces to extend her year’s total to 145, the most on the WTA Tour.
But there were phases near the end when it seemed that might not be enough.??
She had to save two break points at 3-4 in the final set, holding serve with the help of a video review which showed she had landed another ace, and then slipped to love-40 when she was trying to close the match out at 6-5.
Pliskova gambled on hitting flat and hard in a fraught final game, something which paid off as she clawed back four points in a row, and six out of seven, to close the match out.
“I felt tired so I wasn’t expecting it,” said Pliskova, who could rise to a career high world No 12 irrespective of the result of Saturday’s final against either top-seeded Simona Halep, or Caroline Wozniacki, the former world No 1 from Denmark.
“We both have great serves so it doesn’t matter if you go love 30 or love 40 down.”