Emma Raducanu must become more "robust", Great Britain's Billie Jean King Cup captain Anne Keothavong said, after the US Open champion's physical frailties struck again in defeat by the Czech Republic.
The 19-year-old marked her debut in the competition on Friday by beating Tereza Martincova in her first professional match on clay but struggled with a blister on her right foot on Saturday and lost 6-1 6-1 to former French Open finalist Marketa Vondrousova in only 62 minutes.
Raducanu took a medical timeout at the end of the first set before she limped and winced through the second set.
- Raducanu's physical frailties strike again as GB lose BJK Cup tie to Czechs
- 'Raducanu's success caught the whole of tennis by surprise'
- Serena's coach on 'tough time' for Raducanu but why she's on 'right track'
She now faces a race against time to be fit for next week's WTA Tour event in Stuttgart having begun the season playing catch-up after contracting coronavirus.
Raducanu struggled with a blister on her hand at the Australian Open, pulled out during a match in Mexico with a thigh problem and was hampered by a stiff back in Indian Wells.
"It does take time for a player to get used to life on the tour and become more robust, and she certainly needs to become more robust. I don't think that's any secret and she's working on it," said Keothavong.
"The more she puts herself out there, the more she continues to test herself against the very best, she'll figure out a way that works for her."
Despite the blisters, Keothavong did not consider resting Raducanu, saying: "Before the match, we were aware she had a blister but it got progressively worse for her during the match.
"There was no indication of anything that said to us that she couldn't play or that she wasn't ready to go out there and give it her absolute best."
Having gone into the tie as significant underdogs, it was an achievement in itself for Britain to force a deciding doubles rubber, but Harriet Dart and Katie Swan were unable to pull off the upset despite a second-set fightback, losing 6-1 7-5 to Vondrousova and Karolina Muchova.
It is therefore the Czechs, who have been by far the most successful nation in the competition over the last decade, who move forward to November's finals week, although Britain could yet still join them if the Lawn Tennis Association's bid to host the event is successful.
- Stay updated with the latest scores I results
- Updated ATP & WTA rankings
- Get Sky Sports | Download the Sky Sports App
Keothavong had mixed feelings afterwards, saying: "I do feel really proud of all the players and the team effort that's gone into this weekend. The fact that we took it all the way down to the deciding rubber just shows how much guts and courage the players had today. Overall we came close but fell short."
Don't forget to follow us on skysports.com/tennis, our Twitter account @skysportstennis & Sky Sports - on the go! Available to download now on - iPhone & iPad and Android