The chances of a repeat performance in Belfast could hinge on how many defenders O’Neill has left by the time kick-off comes around – with Daniel Lafferty suspended, Craig Cathcart missing with a knee injury and Aaron Hughes (groin) and Ryan McGivern (knock) both rated as “extreme doubts”. Hughes’ injury means three of the four defenders on duty in the morale-boosting 1-0 win over Russia last time out could be missing against Portugal – Lafferty and Cathcart are the others – leaving Gareth McAuley to man for the fort alongside the returning Jonny Evans. McGinn accepts there have been setbacks but is far from downbeat. “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,” the Aberdeen forward said. “You can’t make excuses before the game. We know from training the squad is strong enough to go out and do a good job. We definitely have boys to come in.” Reflecting on the draw in October, and his own part in it, McGinn said: “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. “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.” If Hughes and McGivern do fail to rally in time, O’Neill faces a selection poser. His other defensive options include the uncapped Rory McKeown, the versatile Alex Bruce – who has yet to feature in a competitive match – and Shane Ferguson, who has been deployed in midfield throughout O’Neill’s reign. A maverick solution to the right-back position might even be to deploy the imposing utility man Josh Magennis, despite the fact he has been playing as a striker for Aberdeen in the last two seasons. Pondering his problems, O’Neill told Sky Sports News: “Aaron has a groin problem from the last few minutes against Newcastle. We’re in constant conversation and we left him an extra day with his club, actually. “He’ll report today (Wednesday) and we’ll see how he is, but he’s an extreme doubt. Ryan (McGivern) is the same to be honest, an extreme doubt. “We have Craig Cathcart out too so that limits us slightly. It’ll be a different back four to what we had against Russia and we may have to look at players who wouldn’t have full-back as their natural position. “We have options and I don’t know if I’ll call anyone in, to be honest, but I’ll assess it.” Press Association The sides meet in a World Cup qualifier at Windsor Park on Friday night, with Ronaldo looking to make up for the reverse fixture when Michael O’Neill’s side spoiled the celebrations around his 100th cap by grabbing a 1-1 draw. McGinn was Northern Ireland’s goalscorer in Porto that night, upstaging Ronaldo with a wonderful finish before Helder Postiga levelled in the last 10 minutes. Northern Ireland may be down to the “bare bones” in defence but Niall McGinn has not given up hope of another shock result against Cristiano Ronaldo’s Portugal.