The significance of tonight's Champions League encounter with Ajax has given Neil Lennon much to chew over, although mastication is currently a sore matter for the Celtic manager.
He arrived at Glasgow airport yesterday with a bruised and discoloured face that looked as though it had been on the wrong end of a bar brawl exchange, but it transpired that the marks were the after-effects of an operation to remove a cyst from his jaw.
Lennon also revealed the surgeon had inserted a piece of cow bone into the affected area, inevitably prompting a stream of gags about high stakes and bull headedness. Nevertheless this is an occasion which calls for Celtic to display the bite which has sometimes been lacking in their domestic outings.
Each team feels the other is vulnerable and both are agreed that a win will keep them in the frame to qualify for the knockout stage of this tournament. However, Ajax could not quarry reward from their visit to the east end of Glasgow two weeks ago, so in tennis terms it is advantage Celtic.
"This is an Ajax team that was minutes away from beating AC Milan, so despite their current form not being what it should be they are still a very formidable team at home," said Lennon. "But our away form has been good and I don't think these players fear playing away from home.
"It's a crucial game in the group now and if we can prevail then it sets us up. If we don't then we are in a fight for third place, realistically, but we all want to qualify and we have given ourselves a decent chance of doing that now.
"I thought we played really well in Milan in terms of controlling the game for large periods. I don't remember doing that in my playing days away from home. That was the most galling thing – we ended up losing that game.
"If we can find that level of performance again over here then we will have a chance of doing something, although I think Ajax are a different sort of team. They are younger than Milan and they are more fluent with the ball, so I think it's about how we shape up, win the ball in high areas of the park and use it better on the counter attack than we did against them at home.
"I watched them at the weekend and Vitesse did really well. That has given me a lot of food for thought."
The absence of Scott Brown because of suspension deprives Lennon of his playmaker, but he has been encouraged by the revival in form of Beram Kayal, who scored the winning goal in Celtic's 2-1 home victory over Ajax.
"Brown's a huge loss but I'm hoping Kayal can up his game again like he did at Celtic Park. If he does we should be okay," said Lennon. "Centre midfield is going to be a huge area for both teams.
"The key could be how we attack and if we can find quality at the end of it – because we have quality in the team. With Georgios Samaras and Kris Commons coming back, I think Kris could be pivotal because they don't know him and he might surprise a few of them."
At the other end of the field, Lennon is protective of Fraser Forster and ambitious for his goalkeeper, who has advanced his international credentials in the Champions League, yet has had to exercise patience while waiting for Roy Hodgson to give him an opportunity to win his first England cap, having been called into four squads.
With Joe Hart benched at the Etihad and John Ruddy having to retrieve the ball from his net seven times at the same venue on Saturday, it is permissible to wonder when circumstances will ever be more favourable for Forster.
"Three years ago there is no way you would have envisaged Fraser being in the England squad but he has just improved year in and year out," said Lennon. "He will be a crucial player for us tomorrow.
"It's a big one for him but I don't think it's a make or break game. I said to him, 'You have just got to stay in the moment now.' If he just keeps his form going at this level I can't see him not being picked for one of the friendlies.
"That's for the future. Tomorrow night I need him at his best and he seems to thrive in this environment."
Lennon himself was acutely aware of dismissive attitudes from some observers in England about Celtic's European chances before last season's group campaign. There has been a notable shift in that department and the manager is intent on sustaining momentum.
"I think our performances last year turned a lot of heads," he said. "It was brilliant for us and good for the game up here.
"That has just been carried on this time and I think we have had a really good press down south this time – rightly so." (© Daily Telegraph, London)
Ajax (probable) – Cillesen; Van Rhijn, Moisander, Denswil, Blind; De Jong, Serero, Poulsen; Andersen, Sigthorsson, Fischer.
Celtic (probable) – Forster; Lustig, Ambrose, Van Dijk, Izaguirre; Ledley, Kayal, Mulgrew, Forrest; Commons; Samaras.
Ref – D Aytekin (Germany)
Ajax v Celtic
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