BK Pardubice took the inside track to the Last 16 from Group C by downing visiting Czech rivals BK Prostejov on Wednesday.
Maurice Hampton poured in 22 points and led Pardubice to a 98-84 triumph to leave both sides with 3-2 records.
Because Pardubice have a superior goal differential in their two meetings, they will advance with a victory over BC Goverla (0-5) next week.
Prostejov must travel to Roanne Basket (4-1) for their last game. Should they win and Pardubice fall, then Prostejov would advance.
Pardubice led by as many as 13 points in the opening frame.
Hampton's three-ball made it 29-16 with 27 seconds to go in the period.
The advantage ballooned to 53-35 by half-time when Hampton went in for a lay-up just four seconds before the break.
The lead reached 57-37 after Marcus Arnold made a lay-up early in the third quarter.
Prostejov reeled off 11 unanswered points to close the gap to 57-48, only for the hosts to go back in front 67-48 on a lay-up by Corey Muirhead.
Pardubice's lead never dipped below 13 in the last quarter as they clinched a hugely important victory.
Arnold and Muirhead each had 18 points for Pardubice.
Arvydas Eitutavicius had 21 points in a losing effort.