Czech Republic surged into a 2-0 lead against defending champions United States in the Fed Cup final, despite being without star player Petra Kvitova in Prague.
Barbora Strycova defeated Sofia Kenin 6-7 (5-7) 6-1 6-4 before Katerina Siniakova was more comfortable in a 6-3 7-6 (7-2) win over Alison Riske to put the hosts in a commanding position as they seek to win the tournament for a sixth time in eight years.
The Czechs were already without the injured Karolina Pliskova and were further weakened when the teams for the opening singles rubbers did not include Kvitova due to illness, the world number seven hoping to recover in time for Sunday's action.
Whether she does or not, her team are in a commanding position after a successful Saturday was kicked off by Strycova, who started her last Fed Cup tie with a match against a teenager in Kenin, who was making her debut on an illustrious occasion.
A battling Kenin claimed a dramatic and gruelling opening set that contained four breaks of serve in 64 minutes, a run of four straight points in the tie-break proving crucial.
But Strycova was not broken as she romped to the second set and claimed what proved to be a tense decider having briefly stumbled from a commanding position at 5-2 in front of a patriotic home crowd.
Strycova, who was tearful during the national anthems, said: "It's funny because it's her first tie and my last one.
"For me it was a lot of emotions. 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."
Riske was selected ahead of Danielle Collins, who is ranked above her, but was unable to get the US back on level terms against Siniakova.
A 4-1 deficit in the first set proved too much for Riske to recover from, and while she showed fight to break when her opponent was serving for the match in the second, the American fell 6-1 down in a dreadful tie-break, Siniakova claiming victory with her second match point.