After beating Latvia on Wednesday, GB took on Romania to decide who would take control of Europe/Africa Zone Pool B heading into the final round of games.
Heather Watson, who won her singles match against Latvia, rallied after losing the first set to Sorana Cirstea to complete a 6-7 6-1 6-4 win, edging GB into the lead.
However, Jo Konta was convincingly beaten 6-1 6-4 by Simona Halep to draw things level, before Watson and Jocelyn Rae took part in the doubles decider.
But they could not reverse the Romanian momentum, eventually slipping to a 6-0 6-2 defeat as Romania put themselves in control of the pool.
Watson had been pleased with her performance in the singles earlier in the day, despite the result eventually going against her team.
“Now you can see in my game that I’m a different player,” said Watson. “I’m the aggressor, I’m winning points, I’m not just hoping for my opponent to miss and it is just so much more fun playing like that.
“I think from start to finish that was a really exciting match. I think it was very high-quality – most points were won off winners or forced errors.
“I have played Sorana quite a few times and it is always a battle. I actually think I got better as the match went on.”
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