Martina Hingis carried her professional form to help Switzerland to beat Germany 3-2 and book first Fed Cup semi-finals spot since 1998 on Sunday in Leipzig.
Hingis, 35, who had won the season’s first Grand Slam title with Indian specialist Sania Mirza in Melbourne, partnered Belinda Bencic in the deciding doubles match.
They beat Andrea Petkovic and Anna-Lena Groenefeld 6-3, 6-2 in over an hour to give Switzerland a last four spot.
Playing in the World Group for the first time since 2004, Switzerland will take on defending champions Czech Republic who edged Romania 3-2 for a place in the final.
11th ranked Bencic came from 1-4 down to win the first set tiebreak to beat Australian Open singles champion Angelique Kerber 7-6 (4), 6-3 to give Switzerland a 2-1 lead earlier Sunday.
The Swiss no. one had beaten Petkovic 6-3, 6-4 on Saturday, when Kerber topped Timea Bacsinszky 6-1, 6-3.
Annika Beck pulled Germany level at 2-2 and ensured the first-round contest would be decided by the doubles match when she defeated Bacsinszky 7-5, 6-4 in her Fed Cup debut.