Krystina Pliskova is one match away from following in her sister Karolina's footsteps and winning the Prague Open.
Pliskova comfortably defeated Jelena Ostapenko 6-4 6-2 to ensure there will be Czech finalist in the competition for the third successive year - Karolina triumphing in 2016 after Lucie Safarova won the inaugural event a year prior.
Her task was made somewhat easier by the fact Ostapenko had to finish her quarter-final against Ana Konjuh earlier in the day, completing a 3-6 6-4 6-3 win after play resumed at 1-1 in the decisive set.
Teenager Ostapenko could not carry that momentum into her match with Pliskova, who will face Mona Barthel in the final. The German fought back from a set down to eliminate the highest remaining seed and another home hope Barbora Strycova 3-6 6-2 6-3.
Elsewhere, Francesca Schiavone reached her second successive WTA final by defeating Varvara Lepchenko 7-5 6-4 in the last four of the Grand Prix De SAR La Princesse Lalla Meryem.
It will not be an all-Italian semi-final, though after Sara Errani went down to Anastasia Pavlyuchenkova in straight sets.
The Russian let a 3-0 lead slip in the first as Errani battled back to 4-4, but she won the next eight consecutive games to charge into the final 6-4 6-0.