Four-time Euroleague winners Maccabi Tel Aviv reached the competition's 2014 final after a blistering late fightback gave them a 68-67 win over old rivals CSKA Moscow.
Maccabi will meet either Real Madrid or Barcelona in Sunday's showpiece with the two Spanish giants set to clash in Friday's other semi-final.
The Russian champions, who beat Maccabi in both regular season meetings this term after defeating them in the 2006 and 2008 finals, seemed in control after engineering a 55-40 lead late in the third quarter.
Roared on by a vast majority of the fans in the Mediolanum Forum Arena, Maccabi came storming back in the final period and completed the comeback as guard Tyrese Rice forced a turnover and drove in a lay-up with only five seconds remaining.
CSKA coach Ettore Messina shook his head in disbelief as former NBA forward Sonny Weems missed a difficult three-pointer on the buzzer, condemning the Italian to his first defeat in nine meetings with counterpart David Blatt.
Forward David Blu led Maccabi with 15 points, hitting five three-pointers from nine attempts. Rice added 13 and five rebounds while Ricky Hickman and Alex Tyus chipped in with 10 points each.
Center Sasha Kaun scored 10 of his 14 points for CSKA in the first quarter but fizzled out at crunch time, as did Serbia playmaker Milos Teodosic who netted eight of his 12 points in the second period.