Late replacement Harriet Dart beat Caijsa Hennemann to seal a 3-1 win for Great Britain against Sweden in their Billie Jean King Cup play-off.
Dart was selected by captain Anne Keothavong instead of Jodie Burrage, who had suffered a shock defeat by Kajsa Rinaldo Persson on Saturday.
After Burrage was affected by nerves, Dart thrived on the added pressure to win 7-5 6-2 in London.
Earlier, Katie Boulter had put GB, the overwhelming favourites, 2-1 up.
The British number one was able to avoid Burrage's fate against Rinaldo Persson to deliver a 6-1 7-6 (7-5) win.