Tuesday's tussle in Spain will be Lennon's first trip to the Camp Nou in a managerial capacity, with the opposition facing him a far different prospect from that he encountered in his playing days.
Speaking to The Guardian, Lennon said: "When I played against Barcelona it was in the pre-Lionel Messi days. Xavi was already in the side but he was young and [Andres] Iniesta was on the cusp of the squad. [Barcelona] hadn't really reached the heights when we played them.
"The challenge facing my team is bigger than it was back then. This Barcelona team is two or three gears better than anything I have seen before."
With local rivals Rangers demoted to the Scottish Third Division, Celtic are currently in a league of their own in the Premier League. A 5-0 victory at St Mirren on Saturday put them three points clear of their nearest rivals – with a game in hand on any likely title challengers.
The Bhoys have enjoyed an unbeaten start in Europe too, sitting second in Group G after a home draw with Benfica and 3-2 victory at Spartak Moscow.
As a result, their underdog role against the Catalan giants is unfamiliar territory for Lennon's men.
"They make great teams look ordinary," he said. "The normal instincts of [my] players will be curtailed. Not by choice – just by the sheer force of the players they are going to come up against.
"There is anxiety there. I've thought about nothing else. You are wary of being embarrassed. You don't want that – I certainly don't want that."
Still, despite the task ahead for his side, Lennon is adamant that the Scottish champions will give their Spanish counterparts a run for their money.
"The build-up is great, but from here on in it's just total concentration. We have come here more in hope than expectation but we have nothing to lose.
"We are not here for a holiday or for tourism. We are here to play football. I just want my players to look straight ahead, not look at the side, and try to focus on getting a foothold on the game at some stage."
By Chris Weatherspoon
