With the tie locked at 1-1 overnight in Geneva, there was all to play for on the second day of competition.

But, roared on by a strong home crowd, Switzerland were simply too good.

Bacsinszky's recovery from 5-2 down in the final set against Kristina Mladenovic proved the decisive breakthrough.

The 27-year-old's greater stamina proved crucial as she triumphed 7-6, 4-6, 7-5 in three hours and 17 minutes.

Bencic then won 6-3, 6-4 against Pauline Parmentier to seal and unassailable 3-1 lead.

"It feels amazing," said Bencic after sealing the crucial victory.

"We were so happy when we beat Germany last year and were in the semis. 

"Now we'll try to go to the final."

Switzerland will now seek to improve upon their 3-2 defeat to Czech Republic at the semi-final stage last year.

Belarus will be their last-four opponents this time around after their 4-1 victory over The Netherlands.

They came through despite playing without number one player, Victoria Azarenka, as she takes time out with her baby son. 

Aliaksandra Sasnovich conceded 104 places to Dutch world number 24, Kiki Bertens, but made a mockery of the rankings with a 6-3, 6-4 win.

Eighteen-year-old Aryna Sabalenko then won 7-6, 6-4 over Michaelle Krajicek.

Olga Govortsova and Vera Lapko won the dead doubles rubber 6-4, 6-2 against Dutch duo Cindy Burger and Arantxa Rus.

Defending champions Czech Republic also progressed with a 3-2 win over Spain.

Karolína Plíšková won 6-2, 6-2 against Garbiñe Muguruza before Barbora Strýcová overcame Lara Arruabarrena 6-4, 6-4.

United States won 4-0 over Germany in the final quarter-final tie in Hawaii.