Swiatek holds a 3-2 career lead over Jabeur, with their most recent clash coming in US Open final last year
Iga Swiatek, the world's top-ranked player and defending champion, reached the Stuttgart last-four after defeating 2018 Stuttgart champion Karolina Pliskova 4-6, 6-1, 6-2.
Tunisian world number four Ons Jabeur breezed past Beatriz Haddad Maia of Brazil 6-3, 6-0, setting up a US Open final rematch against Swiatek.
Swiatek had defeated Pliskova without losing a game in the 2021 Rome final, but the Czech took control immediately on Friday, racing to a 4-0 lead in just over a quarter of an hour. Swiatek responded by sweeping the first four games of the second set to level the contest, and after breaking for 2-1 in the decider, she was never troubled again.
Swiatek now holds a 3-2 career lead over Jabeur, with their most recent clash coming in the US Open final last year when the Pole won in straight sets for her second major of 2022.
Jabeur believes that the key to winning against Swiatek is to be unpredictable and not let her anticipate the shots. "The good thing maybe, Iga is not at the same level as she was last year," she said. "I think maybe the key is to be unpredictable with Iga, not knowing which shots I´m going to do. I think that´s really good to disturb her a lot."
World number two Aryna Sabalenka came from a set and a break down to beat Spanish wild card Paula Badosa and reach the semi-finals for the third consecutive year.
The Belarusian won through 4-6, 6-4, 6-4 in two hours and 30 minutes and next meets Russian Anastasia Potapova, who ousted French fourth seed Caroline Garcia 4-6, 6-3, 6-3.
In a tight first set, Badosa saved three break points to serve out, and opened a 6-4, 4-2 lead before Sabalenka broke back for 4-4, reeling off seven games on the trot for a 3-0 lead in the third set.
"The key game was the eighth game in the second set," said Sabalenka of the game that turned the tide in her favor. "I was just talking to myself and saying, 'OK, just try one more time, just try to put the ball back, and then run and move and try to win this game and probably you can win this set. Then who knows what's going to happen in the third set?'"
In the decider, the pair traded serves with five breaks but 31st-ranked Badosa, who fell to Sabalenka in the semi-finals in Stuttgart last year, paid for a string of double faults with nine in total.
Sabalenka sealed victory on her second match point with a backhand into an open court nailing her 40th winner of the day. The Australian Open champion advances to her fourth semi-final in six tournaments this year, with her overall record now 22-3 for 2023.
Sabalenka is looking for her first Stuttgart title after finishing as the runner-up in 2021 to Ashleigh Barty and in 2022 to Swiatek. Potapova, ranked 24th in the world, secured her third top-five win with a 2-hour, 12-minute upset of Garcia.
She hit 19 winners compared to Garcia's 34, but also committed 42 unforced errors, while her seeded opponent made 69.