Sakkari passed Russia’s Anna Kalinskaya in the second round on Thursday, taking the first set 6-2 before Kalinskaya retired in the second set, leading Sakkari 1-0.
Sakkari, who will face Simona Halep in the last eight, continues her breakthrough season in which she finished second at the WTA 500 event in Ostrava, Czech Republic and reached the semifinals of the French and US Open majors.
“I am very proud of myself and my team that we made it to the final for the first time, and for the first time in the history of Greece for a female tennis player,” said Sakkari.
“Until this year I was very hard on myself… Growing, and also getting older and more mature, you see certain things differently.
“Being nice to myself was one of the most important things I changed this year, being nice during the games and the games.”
The number seven in the world is the fifth player to qualify for the Final, which will be held in Guadalajara, Mexico in November, after Ash Barty, Aryna Sabalenka, Barbora Krejcikova and Karolina Pliskova.
The final, which will be contested by the world’s top eight singles and eight doubles teams, was moved from Shenzhen, China, after last year’s event was canceled due to the Covid-19 pandemic.