Top-seeded Ashleigh Barty was taken out by Sara Sorribes Tormo of Spain.

Alcaraz also became the youngest finalist at Umag since Novak Djokovic in 2006.

The American will square off with last week's Hamburg champion for the title in Palermo.

Kristina Kucova roared through eight straight games sparking a 6-0, 6-3 victory over Tamara Korpatsch to reach the BNP Paribas Poland Open title match.

Twenty-year-old Hugo Gaston rallied past Laslo Djere 3-6, 6-3, 6-3 into his first ATP final where he will face Casper Ruud for the Swiss Open Gstaad title.

World No. 1 Novak Djokovic rolled past Hugo Dellien 6-2, 6-2 in his Olympic opener in Tokyo.

Nakashima is the youngest American to reach a final outside of USA since 2002 .