The Aberdeen striker netted in the 1-1 draw between the two sides in October, which was Cristiano Ronaldo’s 100th appearance for his country, and hopes to do the same when he and his teammates meet Ronaldo and co in Belfast on Friday night.
"It was massive. A lot of things came into it... Ronaldo's 100th cap, playing Portugal in their backyard and the fact that no-one gave us a chance,” he told the Daily Record.
"Ronaldo's one of best players in world. He'll be renowned for reaching that milestone of 100 caps for Portugal so for a wee country boy like me from Donaghmore to score on a special night for him was fantastic.
"The boys came away disappointed not to win the game in the end but we know, being realistic, that to come away with a point was fantastic."
McGinn added: "We know it's a massive challenge. We're down to the bare bones defensively but there are boys capable of coming in and doing a good job.
"You can't make excuses before the game. We know from training the squad is strong enough to go out and do good job. We definitely have boys to come in."