MONTHS like this one are why Olivier Ntcham chose Celtic in the summer.

The Frenchman, who turned 22 a couple of weeks ago, was hardly short of options when he decided to leave Manchester City over the summer in pursuit of regular first-team football.

These days, £4.5m is a big outlay for Celtic, but Brendan Rodgers was persuaded to part with that sum for the midfielder, thus forking out the biggest fee he has paid since arriving in Glasgow. It was a bold move for someone who had never played a game for City having spent two seasons in Italy with Genoa on loan where he performed with credit.

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But Celtic were at the front of the queue, they were far from the only admirers, and at first it seemed as if they had signed a world beater.

Ntcham wasn’t just good over his first few games with his new club, he was seriously good. Long and short passing, strong in the tackle, confident on the ball and he scored a few goals as well.

The most encouraging thing about this kid was that he did it in Europe. Ntcham was superb in the Champions League qualifiers, one of Celtic’s best players, and all was well with the world.

The word from inside Celtic was that Ntcham was perhaps not the best trainer in football history but everyone at the club felt there was a serious player in their midst.

But the problem with hitting the ground running is that it is not always possible to keep up the pace.

Ntcham’s form deserted him, so too it seemed, his confidence. He fell out of the team and while this tends to happen with younger players, Celtic are not in a position to justify significant sums on a substitute.

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However, anyone who watched Ntcham strut his stuff against Zenit St Petersburg last week would testify to the player’s ability. Put simply, he was superb, and if he can operate at the same level tomorrow night in Russia, Celtic will have a far better chance of getting through this tie.

Ntcham is a nice big guy, standing beside him you realise what a unit he is, and he exudes a quite self-confidence, which is what anybody needs to make it at the top level of European football.

Should Celtic leave Russia still in the Europa League, this central midfielder is going to be key in terms of how far his club can go.

“If we managed to get through, I think it would be a really big achievement for all of us,” said Ntcham with some understatement. “For the manager, for the club and also for all of the players.

“When you achieve your targets, you are always happy and that is what we want to do. The second leg is going to be tough, but to get through is our aim and that is what we will fight for.

“All of the team enjoyed the first leg because we played good. Defensively, the team was good, and we managed to get the goal which was needed and now we take that to Russia. I think the coach set us up well and it stopped Zenit from making many chances.

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“Four years ago, when I was playing for Manchester City, I went to Russia to play a game against CSKA Moscow. It was with the young team and it was a good game that I enjoyed. Of course, it was a little bit cold, but I liked it.

“Although we have many young players, I feel there is maturity when we are on the pitch. The manager has said that there is growth in the team and I think that is true.”

The 5-3-1-1 or 3-5-1-1 depending on the circumstance worked well last week and it allowed Ntcham to get forward in the knowledge that Scott Brown was minding the shop behind him.

The plan worked and it is going to be interesting to see whether Rodgers sticks with it both at home and in games such as this one.

“It was enjoyable to play in the system,” said Ntcham. “I don’t know how Zenit will be different or if they will be different in the second leg. If they will be stronger than the first leg. Maybe they will change some things for this game, but I don’t know that.

“Of course, they have now played a competitive game after their winter break and, when you play more games, you become stronger and you become more confident.”

A bonus for Rodgers last week was the display of Eboue Kouassi, who has had rotten luck with injury, and a return to form for Moussa Dembele. From the first minute the striker looked on it – for the first time in months.

"Game after game, Kouassi is getting better and we are seeing what he is able to do,” said Ntcham. “And I hope for him and I hope for the team that Moussa can score a goal over in Russia. He was holding the ball up for us a lot in the first leg. When you are a defender, it must be difficult to play against a big and strong striker like Moussa. It must always be hard to come up against that and he is a great player. It is not just down to one player. We all must try to do things, but Moussa can always score and play well, we all know that.”

This is a big test for Celtic and an even bigger opportunity. Zenit are better than they showed in Glasgow and the conditions will have a say. Furthermore, away wins in European competition against any team are to be cherished, so rare are they.

And then there is Aberdeen at Pittodrie this Sunday. Celtic’s season will not be decided over the next five days, but it might well go some way to showing where this team are.