To the surprise of many pundits and fans, the Hoops emerged ahead of Benfica and Spartak Moscow to finish second in Group G behind star-studded Barcelona - whom they famously beat 2-1 at Celtic Park last November - and earn their place in the knockout stages of the tournament for the first time in five seasons.
The Serie A champions, though, are strong favourites to progress through to the quarter-finals but manager Lennon, while recognising the quality of the visitors, said: "I think we have been (underestimated) throughout the whole campaign and going into this game we are being made out to be massive underdogs but I don't quite see it that way myself.
"There is a real belief, anything can happen over two games.
"We go into the tie as underdogs but nothing is going to be decided at the end of 90 minutes tomorrow night, it is over two games and we are prepared to play hard football over 180 minutes.
"They have excellent strikers - Mirko Vucinic, Fabio Quagliarella, Sebastian Giovinco, and they have also brought in Nicolas Anelka.
"But the one who has caught my eye is Alessandro Matri, he looks an excellent young player.
"They are very strong in midfield. Arturo Vidal is playing very well currently, Paul Pogba and Claudio Marchisio, these are class players including Andrea Pirlo who is still one of the finest midfield players in the world.
"So the team is blessed with fantastic footballers but we knew that before the tie or before any preparation were made.
"But it would be dangerous to underestimate Celtic.
"We have proved already this season that we can be a match for anyone."
The former Hoops player, who described Juventus training at Rangers' Murray Park training complex this morning as "irrelevant", recognises the difference between the Italian giants and Barca.
"They are two different cultures," he said.
"Juventus are very strong defensively, very well-organised, very consistent in domestic football and they have been very impressive in their Champions League campaign.
"We have done a lot of work on Juventus and I have seen them myself so we will have to change the way we played against Barcelona but that is only natural because Barcelona dominate possession like no other team."
However, the Northern Irishman expects another momentous European night in the east end of Glasgow.
When he was confirmed as Celtic boss in June 2010, after a spell as caretaker, Lennon said he wanted to "bring the thunder back to this stadium - I want to make it rock again."
In a tweet earlier today, he said:"..think i can hear thunder in the distance" and he expanded upon that at the pre-match press conference.
"This will be one of my best achievements, to bring these nights back to Celtic Park," he said.
"It is the only show around, a European night at Celtic Park.
"It will be a fantastic football arena, for me one of the best atmospheres in world football, never mind European football and it is for our supporters.
"Obviously the players will play their part but to bring these nights back to the club is something that means a lot to me and anyone who has experienced a Champions League night here before will know what I am referring to.
"Obviously we are up against a great team and great coach and it is very exciting for me to challenge myself against Antonio Conte.
"I don't want to fill the players heads too much from a tactical point of view.
"In terms of motivation, I don't think the players need any more from me.
"For some of them, it is probably the biggest game of their young careers and we are hoping we can take the club further in the competition.
"We've always known this has been looming on the horizon so it is almost here and I think we are ready."
Lennon is sweating over the availability of two key players.
Forward Georgios Samaras is battling to recover from a hamstring injury while stopper Efe Ambrose played for Nigeria in their 1-0 African Cup of Nations final win over Burkina Faso last night and will not be back in Glasgow until tomorrow morning.
Left-back Emilio Izaguirre has recovered from a knee injury while winger James Forrest is fit again following a hamstring problem.
The Hoops boss said: "It is as you were with Samaras, we will make a decision on him tomorrow.
"Izaguirre trained today and has joined the squad and Forrest is fit and Ambrose, we expect to arrive tomorrow morning.
"We will see what condition he is in and if he is okay, we will have him in the squad.
"We will give Georgios as much time as he is needed. He has been doing pretty aggressive rehabilitation work and we are hopeful he will be okay.
"If not, then I have a very strong squad and we will have him fit for the second leg."