He said: “I still have confidence and belief in this squad of players and I can see how hard they work on a daily basis.
“Yes, Saturday’s result was very disappointing from the point of view that we made some terrible mistakes but it’s in the past and it’s up to us to cash in on that experience.
“We shot ourselves in the foot with the goals we conceded.
“But I know the players have a strength of character within them and a focus.
“It’s like everything in football – and life – when the going gets tough you have to pick yourself up.”
Lennon revealed how his players will learn from Saturday’s bitter experience and be all the better for it.
He said: “It’s a new day and a new week for us.
“What’s done is done and we have to move on from Saturday.
“Now we have a very important game against Celtic to prepare for and when it comes to games of this magnitude, league form counts for nothing, that’s the romance that this competition brings.
“It’s a one-off game of football and anything can happen.
“In order to try to get a positive result against a club the size of Celtic then we have to try to rediscover that character, belief, work rate and passion that stood us in good stead in our previous league games – prior to Saturday.
“If we can do that, then you never know what might happen at Hampden.”