The World number one beat Croatian Donna Vekic 6-3 4-6 7-6 (7-4) at the Porsche Tennis Grand Prix.
Osaka will now face Anett Kontaveit, who was able to progress after Victoria Azarenka retired.
Petra Kvitova will face Kiki Bertens in the other semi-final.
Erratic Swiatek reaches French Open round three
World number three Iga Swiatek continued her bid to rediscover her best form at the French Open on Wednesday, reaching the third round with a 6-2 6-3 victory over Czech Sara Bejlek in a match littered with unforced errors.
Sinner eases into French Open second round
World number one Jannik Sinner started his campaign for a maiden French Open title in merciless fashion, beating Frenchman Clement Tabur 6-1 6-3 6-4 to reach the second round on Tuesday.
Bengaluru secure IPL final berth after win over Gujarat
Royal Challengers Bengaluru stormed into the Indian Premier League (IPL) final with a commanding 92-run win over Gujarat Titans in qualifier one, powered by captain Rajat Patidar's unbeaten 93 that moved the defending champions closer to a second successive title.
Medvedev stunned by wildcard Walton in French Open first round
Daniil Medvedev could not avoid the French Open first‑round trapdoor as he fell 6-2 1-6 6-1 1-6 6-4 to Australian wildcard Adam Walton on Tuesday in a match marked by sharp swings in momentum on the Parisian clay.
Zee Entertainment in talks to stream FIFA World Cup in India
India's Zee Entertainment is in talks with FIFA to stream and broadcast the 2026 World Cup in the country, the company said in a statement on Tuesday.
