Alison Riske was drawn to play Katerina Siniakova in the second singles match on Saturday on an indoor hardcourt at the O2 Arena.
Riske was selected ahead of Danielle Collins, who is ranked above her, but was unable to get the United States back on level terms against Siniakova.
Yet Czech world No 8 Karolina Pliskova has already pulled out with a calf injury and it is now uncertain whether Kvitova will be appear for a Czech team looking to capture its sixth Fed Cup title since 2011.
Strycova, playing in the last Fed Cup tie, went a set down in Prague to Kenin but won 6-7 (5-7) 6-1 6-4. The Czech dominated it, converting the second match point when Riske sent a backhand wide.
Siniakova had a more straightforward victory as she beat Riske by 6-3 7-6 (7-2).
Siniakova cruised through the first set of her encounter with Riske, forging ahead through a pair of breaks after indulging in groundstrokes and long rallies. And despite the Czechs' remarkable run in the last decade, there is one big statistic weighing in their opponents' favour: The USA has a 10-2 head to head advantage, and has won the last eight meetings in a row.
Barbora Strycova had put the Czechs 1-0 up with a 6-7 (5) 6-1 6-4 win over Fed Cup newcomer Sofia Kenin in the opening rubber. "I believe in all my players up here", she said. She has won four Fed Cups. "I think I definitely do like the court a lot and any time that I'm indoors. I fought for every ball, and I'm so happy I could win today in front of this crowd - it means a lot to me".
The 32-year-old Czech player was more dominant at the net and her stronger serve helped see off the young American.
Leading the United States of America campaign, then, will be No36 Danielle Collins, one of three debutantes with No52 Sofia Kenin and No15 Nicole Melichar.
The U.S., however, will be without Serena and Venus Williams, holders of a combined 30 grand slam singles titles, world number six Sloane Stephens and Madison Keys, semi-finalist at both Roland Garros and Flushing Meadows, in Prague. "The atmosphere was just incredible".
Twice Wimbledon champion Kvitova, whose training has been limited this week due to a high temperature, could still play on Sunday.