And it is, of course, Neil Lennon's debut as manager in this cash-rich tournament.
But despite the fact this is new territory for many of the men involved, they still need to try and find a way to hit the ground running if they are serious about trying to qualify from Group G.
As a player, Neil appeared in the Champions League on many occasions, so he will be able to call upon those experiences to help his players.
He was also first-team coach when Gordon Strachan's team were involved in the group stage four years ago, which will also prove beneficial in this campaign.
When it comes to the players, Scott Brown and Georgios Samaras are the only survivors from the club's last tussles with Europe's elite – and the Greek isn't even fit. Mikael Lustig has also played in the group stage from his time at Rosenborg.
So, as a squad, this is a very inexperienced team at this level of football. You can be sure most of the Benfica squad will have played in the Champions League and sometimes that experience, and know-ledge of playing at such a level, can give teams an advantage.
But I still believe the team Neil has assembled over the last couple of years is more than good enough to go and hold its own in this company.
What they lack in experience in the Champions League, they more than make up for with natural ability and a desire to succeed.
I think a huge benefit to them was the experience of playing in the Europa League last season. At the time, the players maybe did not appreciate just how important and how big a learning curve that campaign would prove.
One of the teams they came up against, Atletico Madrid, went on to win it and they were a smashing side.
They are definitely every bit as good as most of the teams competing in the Champions League, so the games against Benfica and Spartak Moscow will not be much tougher than that.
Udinese, a very strong and well-organised Italian team, also provided Celtic with a stiff test last season, so the fact they ended up being quite unfortunate not to qualify from their group section should instill a degree of confidence in the Parkhead players.
The vast majority of them have played European football and most of them operate at international level as well.
For anyone in any doubt, though, the Champions League is an unforgiving environment – you can't afford to make a mistake or you will get punished.
What Neil will be looking for from his players is to be brave in possession, work hard when they don't have the ball and be disciplined.
More than that, though, he needs them to keep their concentration levels high for the entire 90 minutes. They can't afford to switch off, even for a second.
It will be interesting to see which formation Celtic go with. I'd imagine they will probably be looking at a 4-5-1 set-up, with someone trying to get close to Gary Hooper up front to make sure he isn't isolated.
Or there is also the possibility Lennon might go with a more adventurous 4-3-3 formation with the two wide players basically playing against the Benfica full-backs. By doing so, it would stop them from getting forward and influencing the game. That might be an option.
What you have to be careful of in matches such as tonight's is that you don't focus on the opposition to the extent where you almost forget what your own team's strengths are.
For me, it is important Celtic get in the faces of the Benfica players. I'd urge them to play as high up the park as possible and they might just get their rewards.
A draw wouldn't be the worst result tonight, but a victory would be brilliant.
