• Manager wants his team to be more clinical against Ajax
• Return of James Forrest has boosted Scottish champions
The notion that Celtic have to beat Ajax to keep alive their hopes of progression from Group H is unavoidable. Neil Lennon stopped marginally short of labelling the visit of the Dutch champions as a must-win game, but Celtic's manager admitted defeat would be disastrous.
"If we lose, it would probably end our aspirations to try and qualify," he said. Hints at a points target from the back-to-back fixtures against Ajax followed. "I don't want to look too far ahead but if we could take four out of six, which is a big ask, but doable, we would then have a home game against Milan that I think we could win as well."
Lennon's anxiety over this match is understandable. In order for Celtic to kick-start their campaign they must score for the first time in this group phase and eliminate the profligacy which has been apparent against both Milan and Barcelona. "If we are not ruthless then good teams take advantage of it, as Barcelona did in our previous game," he said.
"We won't dwell on missed chances, I'm just pleased that we are creating them. It's inevitable that the goals will come. We are at home. We want to try and win the game. We will have plenty of attacking options on the pitch."
One of those is likely to be James Forrest, after the young winger came off the Celtic bench to score an equaliser at Hibernian on Saturday. Forrest has been championed by Lennon since the manager's days in charge of Celtic's development team, but a series of injuries have stalled his emergence.
On the night Celtic lost 2-0 in Milan, Forrest was in a hospital bed. Lennon confirmed just how serious Celtic's fears were at that stage. "We first thought it could have been meningitis but thankfully it wasn't as serious as that," he said. "We haven't really got to the bottom of what it was. He lost a stone in weight and scared us all, really. But he has recovered well. The 10 days for the international break gave us a good opportunity to get some conditioning work into him and get his weight back up as well.
"If he is fit and healthy going into the game tomorrow – which we hope he is – then he is good enough to give any team problems."
In the context of Lennon himself, there would be clear significance attached to the defeat of a team managed by Frank de Boer, who is rightly regarded as one of the brightest coaching talents in Europe. De Boer will need little by way of introduction to Celtic, having spent the latter half of the 2003-04 season as a Rangers player. His twin brother, Ronald, was at Ibrox for four years.
"Frank was a class player, as was his brother," Lennon recalled. "They really added to the SPL at the time. Frank de Boer knows the atmosphere, having played here for Rangers in such a high-profile fixture. But I think it's even better under the floodlights, a little bit different. The Celtic-Rangers games were usually early kick-offs, you very rarely got a midweek one.
"Under the floodlights here, the intensity of the atmosphere seems to increase. We have to capitalise on that. We have to try and take the game to Ajax when we can."
Crucial to that plan will be Georgios Samaras, who has emerged as a European specialist for Celtic under Lennon's management. The Greek forward is only under contract until next summer and has been in Glasgow since January 2008. On Monday, the former Manchester City player suggested he would be happy to extend that stay.
"I am fully committed to Celtic," Samaras said. "I feel important and well within myself, with the club and the city and the fans. I am almost 13 years away from my home country and, trust me, it is not easy to be away from family and friends for so long.
"But even in the tough periods, I feel Celtic Park and the club is my home. Both of the sides want me to stay and, in the end, there will be a solution.
"My opinion is if you play in the [English] Premier League at a club finishing 11th or 12th the only thing you will remember when you retire is the money. I don't care about money, that's for sure."