Andre Villas-Boas' men met no resistance in Moscow on Thursday as they scored five goals, to finish the tie 10-3 aggregate winners and advance to the last four
Brazilian striker Hulk gave the visitors the lead early on, and just before the half-time whistle Cristian Rodriguez made it 2-0.
Freddy Guarin got on the scoresheet moments after the restart with a third goal to end the tie as a contest. Artem Dzuba pulled one back for the hosts, but in the following attack Porto got a fourth through star striker Falcao. Substitute Ari scored another consolation for the hosts 20 minutes from time, before Ruben put the final touch on the scoreline with a fifth to round out the result.
The visitors were the more active team early on, pressuring Spartak Moscow high up the pitch. The Russians, however, were the first to create a clear-cut chance as in the 7th minute Aiden McGeady went on a fine run before sending in a venomous strike from the right side of the box, which Helton somehow parried.
Andre Villas-Boas' men received some disturbing news before the half-hour mark when Jorge Fucile had to be substituted after awkwardly falling on his hand. In the 28th minute, however, Hulk gave the visiting fans something to cheer about with a delightful finish from outside the box which left goalkeeper Andriy Dykan helpless.
Porto did not stop there as moments later Cristian Rodriguez wasted a glorious opportunity to make it two. The Uruguayan was superbly released by Falcao in a one-on-one situation with Dykan, but sent his shot wide.
Valery Karpin's struggling team went close through Pavel Yakolev in the 40th minute when the winger showed Cristian Sapunaru a clean set of heels only to see his fearsome shot fly way over the bar.
Spartak Moscow's ascension did not last long as just before the half-time whistle Rodriguez brought the Russians down with a wonderful header after being picked out by Hulk.
Just as the hosts thought things could not get worse, Guarin popped up with the third just after the restart. Falcao was released on the right, and saw his initial finish blocked, but the ball fortunately came back to him and he quickly squared for the Colombian who made no mistake from close range.
Five minutes later, however, Spartak Moscow answered with one of their own. Dzuba made his way through a surprisingly hesitant Porto defence and smashed a superb finish past Helton.
The Russian fans' happiness was short-lived as two minutes later Falcao restored the visitors' three-goal lead after taking advantage of some disappointing defending on a set-piece by the hosts.
Ari popped up with another consolation goal in the 75th minute when he was released by Dzuba, rounded Helton, and managed to find the net from a very tight angle. Spartak Moscow threw everything forward in search of another goal, but instead conceded again with Ruben the man of the moment for Porto.
The in-form Portuguese outfit will now face the winner of Villarreal and Twente's quarter-finals clash in the semi-finals.
Follow Goal.com on . Get the latest football news direct... Check out Goal.com's page; be part of the best football fan community in the world!