Great Britain's hopes of ending a 20-year absence from the top tier of women's team tennis have been dashed in Buenos Aires.
Judy Murray's Fed Cup team were beaten by hosts Argentina, who will retain their place in the eight-nation World Group II next year.
Honours were even at 1-1 after the first days action but Laura Robson, who beat Florencia Molinero 6-1, 6-1 on Saturday, surprisingly lost to Paula Ormaechea.
World number 38 Robson, the highest ranked player on both sides, struggled to hide her disappointment as a player 105 places below her won 6-4, 4-6, 6-2.
Fed Cup newcomer Johanna Konta, who was originally slated to play to fourth rubber, was replaced by experienced British number five Elena Baltacha.
But her lack of competitive action - this was only her second match in nine months - proved decisive as she lost 7-5, 3-6, 6-1 to Maria Irigoyen, meaning the concluding doubles match became a dead rubber.
Great Britain will now return to the Euro/Africa Group and seek to qualify again next February.