American point guard Jordan Farmar proved inspirational for the Israelis, scoring 27 points as Madrid were handed their first loss in the competition this season.
Barcelona, by contrast, were in complete control of their game in Russia against Unics Kazan, winning 93-65.
Erazem Lorbek top-scored for the visitors, scoring 24 points in the rout.
Barcelona remain unbeaten in Group D and boast a better points difference than Siena, who have also triumphed in their first three games.
Brose Baskets of Germany lost a thriller at home to Unicaja Malaga 78-79, with Joel Freeland of Britain providing 18 points and seven rebounds for the visitors.
Bilbao's mixed start to their Group A campaign continued with a 78-69 defeat at the hands of Italian outfit Cantu.
Olimpia Milan had a day to forget, losing a low-scoring game 54-62 to Efes Pilsen in front of their home crowd. The defeat leaves them fifth in Group C while Efes Pilsen climb to second.
Fenerbahce won a nip-and-tuck clash against French visitors Nancy 90-86. It was a much-needed victory for the hosts, who had been winless from their first two games.
There was a first win too for Partizan who held off Belgian side Spirou to record a 91-81 triumph.