Slovakia back in BJK semis for first time since 2013 after eliminating Australia
Hruncakova overcame Kimberly Birrell with a hard-fought 7-5, 6-7(4), 6-3 win in a match lasting two hours and 30 minutes.
Hruncakova, 126 places below Birrell in the rankings, hit 32 winners while the Australian made 37 unforced errors.
World number 43 Sramkova stunned Ajla Tomljanovic with a ruthless performance, beating the former Wimbledon and US Open quarter-finalist 6-1, 6-2. Tomljanovic was struggling with a knee issue.
Slovakia had shocked record 18-time champions the United States on Thursday to reach the quarter-finals.
Slovakia will face either defending champions Canada or Britain for a place in the final. Poland and Italy have booked their places in the last four.