Gambrinus Brno won 75-69 at Ros Casares in Valencia on Wednesday to claim the last remaining place on offer at the EuroLeague Women Final Four.
Jan Bobrovsky's Czech team, champions two years ago, are now two victories away from lifting another title.
Zuzana Zirkova scored 22 points and Tamika Whitmore, a vital member of Spartak Moscow Region's championship-winning side last year, weighed in with 21 to lead the Czech team.
|Katie Douglas finished with 14 points for Ros Casares.|
The Spanish team will be hugely disappointed with the setback.
Ros Casares not only believed they had the team to return to the final they played in last year.
They believed they would win it this time around.
After edging the opener at home over Gambrinus, Ros lost in Brno on Friday and then failed to take the decider despite playing in front of their own fans back at La Fonteta.
Ros Casares began well but Gambrinus, when trailing 12-9 midway through the opening quarter, stole the momentum with a 16-4 run.
That gave Bobrovsky's team a 25-16 lead early in the second quarter and put them in front for the remainder of the contest.
Gambrinus would end up opening up a 38-24 advantage with 2:02 remaining in the first half.
Ros responded with a 16-6 surge, capped by a Marina Ferragut basket, to leave Gambrinus on top, 44-40.
The visitors held their nerve with a Whitmore three-ball putting them back in front by 10 late in the period.
With just 18 seconds to go - two minutes after Delisha Milton-Jones had fouled out with 16 points and 14 rebounds for Ros - the Spanish team managed to pull to within 71-69 on a three-point play by Elena Tornikidou.
Elisa Aguilar fouled Hana Machova, though, and the veteran Czech international made both to re-claim a four-point lead.
Laia Palau, who endured her worst performance of the season by scoring just one point for Ros, missed with a jumper and Zirkova finished off the scoring with a lay-up.
Tornikidou had 16 points and Katie Douglas 14 for Ros, while captain Elisa Aguilar finished with 13 points.
Ros Casares hurt their chances at the free throw line, making 16 of 24 (66.6%) while Gambrinus were 15 of 18 (83.3%).
Gambrinus out-rebounded the hosts 44-37, with Jana Vesela grabbing 13 to go with her 10 points.