ZZ Leiden set up an all-or-nothing showdown with Armia next week in the EuroChallenge by beating BG Göttingen on Wednesday.
The Dutch team won 80-71 and improved to 2-3 while the Violets dropped to 0-5.
Leiden, who lost their encounter to Armia by three points on November 22, need to win against the Georgian club in the second meeting by four to progress to clinch second place in Group B and advance to the Last 16.
Göttingen were the EuroChallenge winners in 2010 but they have been mired in a struggle for a myriad of reasons this season and find themselves battling just to remain in the top flight of Germany.
They had an early 11-6 advantage after a three-pointer by Paris Horne.
The Dutch side responded with a 9-0 run that put them in front to stay.
Thomas Jackson had five points in that spurt for Leiden.
Leiden scored the last four points of the first quarter and the first four of the second to go on top, 23-15.
Seamus Boxley, who had a game-high 27 points for Leiden, already had nine points by then.
By half-time, the Leiden advantage was 40-28 and it grew to 48-35 when Boxley buried a shot from the arc midway through the third quarter.
It reached 53-38 with 2:31 to play in the frame when Boxley buried a jumper, taking his points haul to 21.
Göttingen battled and managed to reduce the arrears to 61-56 when Kyle Bailey scored five straight points.
He hit a shot from long range and followed that with a drive.
Leiden stopped the Violets cold in their tracks with Jackson burying a three-pointer and Boxley dunking.
Gottingen Head Coach Michael Meeks
"Both teams had in the first half a slow start. We knew that they had a disciplined defense. The game slipped through our fingers. I'm satisfied that we showed character and battled back into the game."
ZZ Leiden Head Coach Toon van Helfteren
"I'm satisfied with this game. At the start we had three players who were injured, which meant that we had to alter our technical concept. Two of them could play, so we could play our own game: good defense. Today our offense was great too. It was a good team effort."
Gottingen player Philip Noch
"It was a pity that the game ended too early for us. Some minutes more and we could have won. In the second half we played more focused and I had a good touch with five three-pointers.
ZZ Leiden player Patrick Hilliman
"We did what we had to do. Boxley had a big game and Jackson played well too. I'm glad we have a chance next week against Armia to reach the second round of the EuroChallenge."