Theirs has been the story of the Champions League so far this season. Celtic and romance in Europe's highest competition have always walked hand in hand since Jock Stein led a group of players born within a good jog of Celtic Park to triumph over Internazionale in Lisbon in 1967.
Current manager Neil Lennon has stirred memories of that famous night at the Estadio Nacional, with a run to the knockout stages of this season's tournament. Celtic's budget has been dwarfed by those they have faced, but it has not mattered, their spirit, organisation and tenacity a glowing and growing testimony to Lennon.
They were cruelly defeated in injury-time in the Nou Camp. The 2-1 victory against Barcelona in the return leg at Celtic Park will go down as one of the greatest upsets seen in European football for years. It has taken Celtic to the knockout stage of the competition for the first time in five seasons.
Now Lennon wants to avoid the remaining giants of European football, including Manchester United, as the Scottish Premier League leaders look to carry their form beyond the final 16 of the Champions League, in today's draw in Nyon.
"In Europe you never really feel confident," he said. "You always worry about all the opposition. I would like to avoid the big guns, I say big guns, but they're all big guns.
"Bayern Munich are a tough, top team, Manchester United, obviously, and Juventus, who have been pretty consistent for a few seasons. Dortmund have been excellent over the last couple of years as well.
"Malaga spent a lot of money. Whether they will have to sell in January, we will have to wait and see. PSG are probably relative newcomers but they are well backed. Schalke have pedigree, they made the semi-final in 2011. If we can avoid the top four and one of those three, you might think we have a chance over two games. Look, whatever the draw brings, we will analyse it to death to get the team ready for whatever comes.
"We have got through the psychological barrier of winning away from home as well now."
For the first time in the Champions League, the reigning champions have not reached the stage where the competition really starts to get interesting. Robert Di Matteo paid for non-qualification for this stage with his job at Chelsea, but in such a rarified atmosphere, the failures match the rewards. Manchester City, the champions of England, will similarly feel the real pain of failing to get out of the qualification group today. For them, there is not even the fallback of the Europa League, although their bid to retain the league title may yet benefit from that secondary slip-up.
The absence of Chelsea is more notable given the amount of teams left at this stage who have already lifted the trophy. More than half (nine) of the remaining 16 teams have won Europe's premier competition at some point in their history.
The eight group winners will be paired against the eight runners-up in two-legged ties that will be played in February. Manchester United, who won Group H, cannot, however, be paired with another club from the same country at this stage of the competition. Thus, there will not be a battle of England against Arsenal, who finished runners-up in Group B. United could, however, as Lennon alluded to, face Celtic, who were runners up in Group G. United could also be paired with Porto, Milan, Real Madrid (who they were picked to face in a rehearsal draw yesterday), Shakhtar Donetsk or Valencia. Sir Alex Ferguson's side won their first four group games, before two relatively meaningless defeats.
For Arsenal, the cost of not winning their group becomes apparent at 10.30am today. The list of potential opponents is a who's who of European powerhouses. It could be Paris St-Germain, Barcelona, Juventus, Bayern Munich, Borussia Dortmund or Malaga. However, Arsène Wenger will know only too well of the calming nature a Champions League run can have on a troubled domestic campaign.
Celtic and Lennon similarly face giants wherever they turn. They could take on any of Arsenal's opponents, apart from Barcelona. Instead, they have Schalke and United to contend with. In their favour is the fact that Celtic Park is a European fortress that few clubs in the draw will feel particularly pleased about heading to.
Beating Barcelona has been the story of this year's competition by a country mile. By lunchtime today, however, some of European football's true giants will be concerned about their very future in the competition.
The seeding pots for the draw are as follows:
Group winners: Paris Saint-Germain FC (FRA), FC Schalke 04 (GER), Málaga CF (ESP), Borussia Dortmund (GER), Juventus (ITA), FC Bayern München (GER), FC Barcelona (ESP), Manchester United FC (ENG)
Group runners-up: FC Porto (POR), Arsenal FC (ENG), AC Milan (ITA), Real Madrid CF (ESP), FC Shakhtar Donetsk (UKR), Valencia CF (ESP), Celtic FC (SCO), Galatasaray AŞ (TUR)