Prague, US Open champion Emma Raducanu won on her Billie Jean King Cup debut here on Friday to help Britain level with the Czech Republic and leave the qualifying tie delicately poised.
The 19-year old Raducanu was playing her first senior match on clay and she won 7-5, 7-5 against world number 50 Tereza Martincova.
The teenager saved a set point at 5-4 in the opener before winning the next three games, and also fought back from a 4-1 deficit in the second against the 27-year-old Martincova Raducanu won six of the final seven games to clinch a vital victory for herself and her team.
With her victory, she levelled the best-of-five tie after Harriet Dart lost 6-1, 6-0 to Marketa Vondrousova.
"This one means so much to me. Playing on clay definitely took some adjusting, even now. The conditions were very windy and some bad bounces, so to adjust and adapt in the situation was very challenging but I'm very proud of how I dug in," said world number 12 Raducanu, who is set to play Vondrousova in the reverse singles on Saturday.
"In the beginning of the second set, I went a bit flat and everyone in my team was telling me the intensity had dropped. It is difficult to regain that but I'm very happy I did in the end," she added.
The countries will play two singles matches on Saturday, plus a doubles if needed. The winners will qualify for November's finals, while the runners-up face a play-off tie the same week.
Britain are among the countries bidding to host the finals and could also still qualify as the host nation.