Emma Raducanu made a winning return from injury before Katie Boulter followed with another victory to secure Great Britain's place in the Billie Jean King Cup quarter-finals.
In the opening match of Britain's first-round tie against Germany, Raducanu secured a 6-4 6-4 victory - on her sixth match point after an edgy finish - over Jule Niemeier in Malaga.
The 22-year-old was playing her first match in almost two months because of a foot injury, but produced an encouraging display in the 12-nation women's team event on her latest comeback.
With Raducanu and Boulter ranked higher than each of their singles opponents, Britain were considered the favourites against Germany.