Sakkari was trailing Alexandrova 4-1 in the first set when she could not go on. Tournament organisers said the Greek cited dizziness.

Sakkari is ranked seventh in the world and secured a place at the season-ending WTA Finals earlier this week when she reached the quarter-finals in Moscow.

Alexandrova reached her first tour-level final since winning the Shenzhen Open in January 2020 and has a 1-1 career record in finals.

In Sunday's final, Kontaveit will bid to win a third title in as many months after beating Marketa Vondrousova 6-3 6-4 in their last-four encounter.

Estonian Kontaveit took a big lead early in both sets and closed it out on her fourth match point.

"I thought it was a very difficult match. I was trying my hardest and Marketa is such a nice girl and a tough opponent and a tricky opponent to play against," Kontaveit said.

"I'm so happy to be in the final."

Kontaveit holds a 1-0 career record over Alexandrova, with a win at last year's Ostrava Open.

Australian Associated Press