With all of their big players now on board, chiefly Lauren Jackson of Australia and Sue Bird, Diana Taurasi and Tina Thompson of Team USA, Spartak won 85-76 to join Gambrinus on 3-1 at the top of Group C.
Taurasi had 32 points and six rebounds for Spartak.
Kosit 2013 suffered a 62-58 home defeat to US Valenciennes, who got 16 points, eight rebounds and three assists from their Italy international playmaker Francesca Zara.
USVO improved to 2-2 while Kosit are 1-3.
In Group A, CSKA Moscow marched to a 109-69 triumph over Fenerbahce to remain undefeated at 4-0 and TTT Riga won 77-66 over MKB Euroleasing of Hunary.
TTT Riga, MKB Euroleasing Sopron and Fenerbahce are all 2-2.
Jolly JBS Sibenik claimed a big win in Group B, 65-64 over Wisla Can-Pack.
Bourges Basket, meanwhile, suffered a 57- 56 defeat at home to unbeaten UMMC Ekaterinburg.
Wisla Can-Pack Krakow and Croatians Jolly are 2-2 while Bourges, who reached the Final Four last season, are 1-3.
There were also thrillers in Group D.
Ros Casares fell behind late in the fourth quarter after a basket by Nykesha Sales of TEO Vilnius, but rallied for a 75-70 victory to improve to 4-0.
USO Basket Mondeville claimed their first win, 91-62 over struggling Dynamo Moscow and Germano Zama Faenza 68-66 at home to MiZo Pécs 2010.
Ros are top of the pile with MiZo Pécs and Dynamo 2-2.
USO Mondeville Basket, TEO Vilnius and Germano Zama Faenza are all 1-3.