Just hours after Paolini beat tearful Croatian Donna Vekic 2-6, 6-4, 7-6(8) in the longest women's semi-final at the All England Club, it was Krejcikova's turn to dig deep for victory against fourth-seeded Rybakina in two hours and seven minutes on Centre Court.
Krejcikova faces seventh seed Paolini on Saturday in what will be the second Grand Slam final of her career after her French Open triumph in 2021.
"I'm so proud about my game and my fighting spirit today," said Krejcikova.
The Czech started 2024 with a run to the quarter-finals of the Australian Open, but a first-round exit at the French Open was a major setback.
She struggled with a back injury and illness, winning just three singles matches in the five months before finally finding her form in remarkable style at Wimbledon.
Krejcikova shocked 11th seed Danielle Collins in the fourth round and former French Open champion Jelena Ostapenko in the quarter-finals, before turning her sights on Rybakina.
The two-time Wimbledon doubles champion is now one win away from an unexpected triumph in the singles.
"Unbelievable. It is very tough to explain, but a lot of joy and a lot of emotions," Krejcikova said.
"When I broke her in the second set, I started to be in the zone and I didn't want to leave the zone."
Rybakina had been in formidable form, dropping just one set as she extended her impressive All England Club record to 19 wins from 21 matches.
Rybakina, who won Wimbledon in 2022, made a fast start with two quick breaks for an early 4-0 lead in a one-sided first set against Krejcikova.
In her first Wimbledon semi-final, Krejcikova turned the tide in the second set, landing a priceless break in the sixth game.
She levelled the match on her sixth set point, making it the first time in 20 years that both Wimbledon women's semi-finals had gone to the final set.
The Czech held all the momentum and she eventually wore down Rybakina, who had committed over 35 unforced errors by the time she surrendered her serve in the decisive, seventh game of the final set.
