The manager remains wary of his side's Group H opponents despite their win two weeks ago, and insists he will be content with a draw in the Amsterdam ArenA on Wednesday
The Scottish giants sit third their Champions League group heading into Wednesday's encounter, knowing a repeat of the 2-1 win at Parkhead a fortnight ago, coupled with a loss for Milan at Camp Nou, will move them into second place.
However, Lennon is taking nothing for granted ahead of the "pivotal" clash and admits just a point would be mark a success in Amsterdam.
"We always knew that the double-header against Ajax would be pivotal and it has proved to be the case," he told reporters.
"You don't know what is round the corner but what I would say is that on their day Ajax are as good as Barcelona and Milan.
"They caused us as many problems as both those teams and I think it will be the same on Wednesday night.
"I think it was important that we got some points on the board against Ajax. But we are under no illusions as to how difficult this will be. Ajax were very unfortunate not to beat Milan here."
Lennon went on to note that whilst it is vital for Celtic to not come away empty-handed, he will remain confident of progressing to the knockout stages if his team do not lose.
"I think the Champions League inspires players and gets the best out of them, and I hope that is the case for our players," he continued.
"If we are to progress we have to pick something up away but we don't need to win. If we can get a point and beat Milan at home that gives us seven points and gives us a real chance of qualifying."