In the opening minutes after the restart, Shakhtar were perhaps unlucky not to be awarded a penalty, when Alessandro Bastoni's booted clearance from deep in his own area struck the arm of the unaware Roberto Gagliardini. The referee, however, waved play on.
Moments later, the dramatics were at the other end, when only a spectacular save from Pyatov kept Martinez from doubling Inter's advantage, getting his fingertips to the Argentina international's ambitious and goal-bound chip.
Moraes nearly levelled the score on the hour mark, but his point-blank header struck Samir Handanovic directly in the hands, and the Nerazzurri goalkeeper quickly gathered up the ball before the Shakhtar No. 10 could pounce on the rebound.
Martinez added his second goal of the night, all but securing Inter's place in the final, with little more than 15 minutes to play, wrong-footing Sergey Krivtsov and curling a strike into the far corner. In the next nine minutes, Romelu Lukaku would add a pair of goals to make for a lopsided scoreline in favour of Antonio Conte & Co.
A win in Friday's final would see Inter lift their first continental trophy since their famous Champions League title under Jose Mourinho in 2010.