Teenage qualifier Amanda Anisimova shocked number one seed Zhang Shuai at the Japan Women's Open to reach her first WTA final.

The American, who turned 17 a fortnight ago, becomes the youngest player to make a final since Donna Vekic, aged 16, in 2013.

In a match interrupted by two lengthy rain suspensions she won 7-6 7-5 in a one hour and 48 minutes.

Anisimova will face second seed Hsieh Su-Wei after she had to win twice in the day to book her place.

After overcoming Ajla Tomljanovic 4-6 6-2 6-0 in a quarter-final held over from Friday because of rain she returned later on to beat Wang Qiang 6-4 6-4.

Qualifier Jessica Pegula produced an upset at the Coupe Banque Nationale as she put an end to the seven-match winning streak of number two seed Petra Martic.

The world number 227 produced a confident display, winning 85% of her first serve points to topple her Croatian opponent 6-3 7-5 and book her place in the semi-finals.

Pegula needed just one break of serve off the back of a double fault from Martic to close out the opening set, while the second set saw the pair exchange breaks

With the scores tied at 5-5, the American played aggressively to go 6-5 up before holding her nerve to serve out the match.

She will now face a meeting with compatriot Sofia Kenin, who reached the second WTA semi-final of her career by ousting number three seed Monica Puig.

The 19-year-old hit six aces and lost just six points on serve as she dismissed the Puerto Rican 6-3 6-1 in 55 minutes.

As the number five seed, Kenin is now the highest-ranked player left in the draw in Quebec.

British number three Heather Watson sealed her spot in the final four with a straight-sets win over Canada's Rebecca Marino.

Watson took two breaks – losing her own serve once – to take a one-set lead, before needing just one break in the second to clinch the match 6-3 6-4.

Up next for the Briton is Pauline Parmentier, who beat American Varvara Lepchenko 7-6 (7/5) 6-1.