The Parkhead manager's stature has grown with every season he has been at the helm and he has taken great personal satisfaction at watching the team he has assembled with a limited budget punch above their weight by reaching the last 16 of the competition.
In particular, the positive approach he has adopted in Europe and the style of football his team have produced has further enhanced his reputation as Lennon has no doubt attracted the attention of one or two clubs south of the border just like many of his players.
With the dust now settled on his side's Champions League exploits, Lennon was in reflective mood as he was asked what he has proven during this campaign.
"One, I can manage at this level and two, that we can compete very well at this level," said the former Hoops captain.
"As a coach, I feel I have shown a lot because there were so many question marks hanging over my head, even when I took the job. 'Rookie manager' was thrown at me for a long time. Once you win the league that gives you a bit of comfort in a job like this.
"Then obviously the qualification into the group stages was massive. I felt we had a good enough team to compete and we have certainly done that.
"The football we have played at times has been of a very high order. We just came up a bit short on Wednesday night in some areas and there's no shame in that.
"I thought we had good spells in the game. We needed to score when we had Juventus on the back foot a little bit. I don't think we were really ever uncomfortable in the game.
"Buffon's made a good save and the one Samaras flashed across the goal, you're just waiting for Hooper tapping that in, and we would have been back in the game.
"If Ambrose could head it then both ties would have been different. I mean, he's missed another one from four yards out.
"That would have made the game one each. I didn't expect to win the tie, but at 1-1 you think 'can we go and win the game now?', but it wasn't to be."
This is the third occasion Celtic have managed to reach the last 16 of the competition and failed to progress any further but Lennon doesn't believe that is as far as the club can ever hope to reach.
He said: "It depends on the draw I think. If you get the luck of the draw, there are some other teams I think we're on a par with like Galatasaray and Schalke. But the gulf in size of squads and certainly the money that they've spent is big.
"It was a big ask to do it over the two games, particularly after being 3-0 down. We never gave ourselves a chance for this one with the scoreline from the first game.
"Should Celtic be in the group stages every year? It depends. It's such a difficult thing to do. You're two or three weeks into your pre-season and you've got the qualifiers. I think it's a huge ask.
"Maybe further down the line if the co-efficient gets better it might make it easier but we are the fourth team to do it in the last 10 years.
"It's not bad for a league the size of ours."