The Russian side take a 1-0 lead in the best-of-five series, and a huge boost going into game two on Friday.
There were points contributions from across the team, with Nenad Krstic adding 18 points, Alexey Shved 15 and Jamont Gordon 14.
The first quarter was relatively even, with just a point separating the two sides, but having taken a 10-point lead by the halfway point, CSKA savaged their opponents 34-11 in the third period to settle the contest long before the final buzzer.
The second of the night’s matches saw
Vassilis Spanoulis fouled out with five minutes remaining and hosts Montepaschi Siena leading 70-67 but Acie Law stepped up with five points and an assist before the buzzer.
Joey Dorsey also impressed in the dying seconds while Georgios Printezis capped a stunning performance with 20 points for the Reds.