Earlier on Friday, Rybakina booked her last-four spot by defeating Italy’s Jasmine Paolini 6-3 5-7 6-3.
On the opposite facet of the draw, Wimbledon champion Marketa Vondrousova knocked out world quantity two Aryna Sabalenka with a 3-6 6-3 7-5 win.
Sabalenka has did not transcend the quarter-finals of a match since her Australian Open triumph in January.
The Belarusian, a runner-up within the final three Stuttgart tournaments, dedicated 48 unforced errors and transformed simply six of her 15 break factors.
Vondrousova, the Czech sixth seed, will play Marta Kostyuk subsequent after the Ukrainian secured her second straight top-10 win in opposition to US Open champion Coco Gauff.
American Gauff sped via the primary set in 36 minutes, however Kostyuk, who knocked out China’s fifth seed Zheng Qinwen on Thursday, fought again from a break down in each the second and third units to win 3-6 6-4 7-6 (8-6).