Germany's former world No.1 Angelique Kerber won her eighth consecutive match on Friday and will play Australian Ashleigh Barty in the final of the Sydney International.
Kerber, who began last year as No.1 before finishing at No.22, continued her 2018 resurgence with a 6-2, 6-3 win over Camila Giorgi, ending the Italian qualifier's run of six wins in the tournament.
It is an impressive start to the new year for Kerber, having won her four matches at last week's mixed teams Hopman Cup in Perth before her four victories in Sydney.
"Ash is a great player. She played unbelievable last year," Kerber said.
"I played the last match of 2017 against her, so it was not so long ago. I know what to expect."
Barty will play in her first home WTA final on Saturday after she beat compatriot Daria Gavrilova 3-6, 6-4, 6-2.
It will be the 19th-ranked Barty's second career title and her win over the 25th-ranked Gavrilova came after a topsy-turvy match that included 11 breaks of serve.
Kerber and Barty have split their two previous meetings last year with the Australian winning in Zhuhai, China, and the German winning in three sets in Brisbane last week.
Barty continued her strong buildup to next week's Australian Open in Melbourne, where she opens against world No.69 Aryna Sabalenka.
"It's nice to make a final at home, but I think in my eyes it's perfect preparation for next week," Barty said.
"I mean, I'd love to go one further and hold the trophy up here, but I love playing in Australia, I love playing at home.
"It's nice to be able to get a lot of matches here and be rewarded with the final."
Russian qualifier Daniil Medvedev upset Italian fourth seed Fabio Fognini 2-6, 6-4, 6-1 to reach the Sydney men's final.
The 84th-ranked Medvedev came back from a set down to move within one win of what would be his maiden ATP title against rising Australian star Alex de Minaur.
"I'm very happy, first of all, because life on ATP Tour is not easy. Every match you win, you're glad to win it, no matter first round, second, so it goes step by step," Medvedev said.
"To win here six matches in a row, to be in my second ATP final, to have the chance to get the title is amazing feeling. I'm just motivated to do it."
Eighteen-year-old de Minaur continued his extraordinary run of results in the lead-up to the Australian Open with a 4-6, 6-1, 6-1 win over Frenchman Benoit Paire.
De Minaur stunned fourth seed Milos Raonic in the second round on his way to reaching the Brisbane International semi-finals last week before losing to American Ryan Harrison.