As the momentum has continued to build for Stephen Kenny's Ireland side since that dramatic night in Faro, there remains the strong possibility that the rematch with Portugal in Dublin tonight could do it some damage.
Two late Cristiano Ronaldo goals in September’s World Cup qualifier denied Ireland victory on the Algarve coast, however, it was the way the team performed that really opened the nation’s eyes to the potential of what could be achieved under the new regime.
Calm and composed, organised and efficient, Ireland’s performance against a side capable of mixing it with the very best was rightly lauded, and even the minor mishap, when the team were punished with a penalty playing out from the back, was quickly rectified as Gavin Bazunu stopped Ronaldo’s spot-kick.
Granted, there was a natural lull in the following game, at home to Azerbaijan, but Kenny’s side then put in an entirely different, yet equally impressive showing at home to Serbia as they defended resolutely, weathered the prolonged storm, before hitting back late in the game to secure a deserved draw.
If it started in September - many would argue that the summer camp in June proved just as important - the October window saw this Ireland team emerge as a really confident unit, with the belief to win games in style.
Azerbaijan away saw Ireland take the game to their opponents, grab an early goal and all but seal the three points by half-time.
Qatar at home followed, and while the quality of opponent may be taken into consideration, the overall performance went up another notch, as the confidence was evident with the team playing some sensational football for large spells of the game.
But Portugal are a different level and have the potential to certainly stall the progress that has been made over the past few months.
Not just a team, but an entire squad of top-quality players, Portugal have an abundance of talent and will again be favourites to win the Dublin encounter.
But there are certain circumstances that could work in Ireland’s favour going into the game and will level the playing field to a degree, at least.
While Ireland are playing for pride and progress, for Portugal, World Cup qualification is not yet secured and they couldn’t have asked for a tougher end to their campaign.
A tricky task in Dublin to negotiate ahead of the group decider against Serbia on Sunday, and with the other Group A challengers idle on Thursday, Portugal will be looking to do the minimum against Kenny’s side to garner a favourable result.
The first game against the Boys in Green will have opened their eyes to the fact that they cannot just expect to turn up and take the points, however, they will be mindful that a draw is all that is needed.
Portugal would find it very hard to contemplate losing to Ireland, even with a weakened side, and while complacency should not be an issue, they could certainly be tempted to rest a couple of players sitting on yellow cards.
Six players in total risk missing the Serbia encounter, while Bernardo Silva has already been ruled out tonight injured.
And this Portugal side also have to contend with the fact that they are often criticised for not being as good as the sum of their parts, while the coach has faced criticism for not getting enough out of the attacking options that he has at his disposal.
Ireland, on the other hand, continue to look as low as League 1 in England to complete their squad, and while it was a long, hard year in the making, Kenny’s side are now certainly looking like a unit who have the potential to play above their station.
Kenny has decided on his preferred system and is gradually anointing a string of regulars, which is giving a very familiar look to his team and creating continuity.
Andrew Omobamidele looks set to miss out on the game as he nurses an Achilles injury, which will upset the central defensive trio, however, the manager should look to Seamus Coleman to slot into a more central position, allowing both the captain and Matt Doherty to line out in the same XI.
Shane Duffy and John Egan will make up that trio, and it looks a straight shootout between James McClean and Enda Stevens for that left wing-back position.
Stevens would have been nailed on for the role some months back, but competition for places has really increased over the past three months and McClean has proved a bit of a favourite for the manager in recent games.
McClean’s energy and enthusiasm makes up for the odd rash challenge or misplaced pass, and with a narrower attacking unit set to be employed, McClean would have the freedom of the flank to carry out manoeuvres.
Either way, such is the demand on running in that role, there is a good chance that the workload will be shared between the two over the course of the 90.
Josh Cullen is now considered one of the first names on the team-sheet, while Jeff Hendrick is becoming a real driving force in getting the team to play the Kenny way.
"In the last four internationals Jeff has really raised his game," said Kenny, speaking at the pre-match press conference. "He has been really consistent. It’s great for us, and we can see the benefits of that and hopefully he can bring it into tomorrow."
Kenny is unlikely to ask a two-man midfield to try to cope with the strength of a free-flowing Portugal midfield, and will surely look to another grafter in the middle of the park, which would see Conor Hourihane, Jason Knight or Alan Browne getting the nod.
All three have impressed when handed opportunities for the manager and offer different attributes in what will be a high-octane department tonight.
Both wing-backs will also be asked to tuck in and help out at times as Ireland look to crowd out that vital area where Portugal create and conjure when afforded the space.
Callum Robinson has had a stop-start year since Kenny took over, however, the last two games have firmly placed a huge amount of expectation on his shoulders.
Five goals in two games in October sees the West Brom forward bursting with confidence going into the game and Robinson will be afforded a free role in attack to look to exploit space and take chances.
Adam Idah is another who established himself in the early part of the Kenny era, however, Chiedozie Ogbene has now emerged as a real alternative to the Norwich striker.
Former Cork City forward, Ogbene brings a different approach to the attacking unit compared with Idah’s more direct running, and again there is a strong likelihood that the two will both play a part throughout the 90 minutes.
The manager said that his side have to earn the right to control the game by remaining calm and playing with intelligence throughout, and while the plan in Portugal worked well for 88 minutes, this time the manager is hoping to make a tweak or two to see out the full 90.
"We had a gameplan and it worked really, really well, up to the 88th minute. We'd kept Cristiano Ronaldo quiet for the whole game," said Jeff Hendrick, speaking at the pre-match press conference.
"We have to try and put out that same level of commitment and hard work, we didn't do too much wrong out there, we’ve been working hard on what we can improve on that performance, and hopefully we can put that right."
Putting that right will involve the near-impossible task of keeping Ronaldo’s feet on the ground, such is his aerial prowess, that he is virtually unstoppable when he gets a run at an arriving cross.
And while the manager also emphasised the fact that his side cannot just focus on one player, it suggests that the best way to stop the Manchester United man is to cut off his supply.
Late lapses cost Ireland dearly in Portugal as Ronaldo reigned supreme, however, this time the Ireland XI will have 50,000-odd supporters keeping them on their toes, and the manager is hopeful that his team can put themselves in a position to allow the crowd to roar them home.
Follow the Republic of Ireland v Portugal via our liveblog on RTÉ.ie/sport and the RTÉ News app, watch live on RTÉ 2 and the RTÉ Player, or listen to live radio commentary on 2fm's Game On.