The Parkhead side are within 180 minutes of making it in to the lucrative group stages of the competition for the second successive year.
The Hoops boss believes the experience of getting through the same stage last season will stand him in good stead but is keenly aware of what is at stake.
"I suppose after last year you are a little more comfortable," he said.
"But it is still quite a nerve-wracking time for all us involved although we try not to let that permeate to the players.
"We are relaxed, we had a great result at the weekend against Aberdeen and the players are in good form and looking forward to the game.
"We haven't had much time to gauge but I am very happy with the way the squad has settled. I have liked the camaraderie between the players and the new boys have settled in very well.
"Obviously we have lost hugely influential players in Victor Wanyama, Gary Hooper and Kelvin Wilson but we feel have acquired some very good players. They will take time to bed in obviously, but we are very happy with the way things are going at the moment."
At his press conference on Monday, Shakhter's Russian boss Viktor Kumykov described the Scottish champions as the master in comparison to his students but the Celtic manager was not fooled by the rhetoric.
"Obviously we have more experience than Shakhter but they are at home and they have an excellent home record," he said.
"They have already knocked out BATE Borisov, who beat Bayern Munich in the Champions League last season, so this is going to be a difficult tie."
Kumykov said: "This game is going to be very difficult for us.
"We are newcomers to the Champions League, Celtic is a very experienced club and are former champions of Europe.
"Our main task is to obtain Champions League experience.
"We recognise that Celtic are more experienced and stronger than us.
"But football is illogical and you cannot be sure about anything.
"In football, the strongest side does not always win and there aremany examples of that, even in the Champions League."