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.
Mexico bounce Czechs out of World Cup with win
Mexico have continued their perfect start to the World Cup with a 3-0 romp against the Czech Republic on Wednesday, finishing their group-stage campaign with a flourish and killing off their tame opponents' hopes of making the knockouts.
South Africa beat South Korea to reach World Cup knockout stage for first time
South Africa have reached the knockout phase at a World Cup for the first time on Wednesday when Thapelo Maseko's second-half strike gave them a 1-0 win against South Korea, who can still qualify as one of the best third-placed teams.
Qatar’s Assim Madibo gets 5-game ban for injuring Canada's Ismael Kone
Assim Madibo has received a five-game suspension from FIFA's Disciplinary Committee on Wednesday, following the Qatar midfielder's tackle that injured Canada midfielder Ismael Kone.
Morocco earn comeback win over Haiti to reach last 32 as group runners-up
Morocco have confirmed their progress to the World Cup last 32 but twice had to come from behind to get the better of plucky Haiti with a 4-2 win in an action-packed game on Wednesday, and fell short of topping Brazil in the Group C standings.
Vinicius fires Brazil into World Cup knockouts with win over Scotland
Brazil has moved up to the World Cup knockout stages with a commanding 3-0 win over Scotland on Wednesday, as Vinicius Jr netted twice and Neymar made his first appearance in a Brazil shirt in nearly three years.
Dubai government employees will once again benefit from flexible working arrangements this summer, as the 2026 edition of the 'Our Flexible Summer' initiative comes into effect from June 29 to September 10.
UAE President His Highness Sheikh Mohamed bin Zayed Al Nahyan has met with US Secretary of State Marco Rubio, who visited the UAE as part of a wider Middle East tour.
Sheikh Abdullah bin Zayed Al Nahyan, Deputy Prime Minister and Minister of Foreign Affairs, has held bilateral talks with the UK's Foreign Secretary Yvette Cooper in a call on Wednesday.
