The Polish top seed defeated the 17th-ranked Czech player 4-6, 6-1, 6-2 in just over two hours in the quarterfinals of the women's singles on Friday.
Świątek, who is defending her title at the clay-court tournament in Stuttgart, will now face Ons Jabeur of Tunisia for a place in the final.
The 21-year-old Pole, coached by countryman Tomasz Wiktorowski, has topped the Women's Tennis Association's (WTA) world rankings since April last year.
The Polish player in February won the Qatar Open tournament in Doha to claim her 12th career singles title.
(gs)
Source: IAR, PAP, Canal+