When the draw for Group C was made there was feeling of Mission Impossible for Celtic.

The weight of Barcelona and Manchester City hung heavy over the group, while Borussia Monchengladbach who finished fourth in the Bunsdesliga last season were also regarded as dark horses given the season they enjoyed in Germany last year.

When Celtic defender Erik Sviatchchenko headed home on the last international break, it wasn’t just all about Denmark; given that two of his countrymen form the Borussia defence, there was something of an undercover spying session going on.

Borussia Monchengladbach defenders Andreas Christensen and Jannik Vestergaard have restricted Sviatchenko to a place on the subs bench for his country, and although the former is out of tonight’s game at Celtic Park there was still a deliberate ploy to exact details from him on the quiet.

“We all spoke the last time we were with the national team,” smiled Sviatchenko. “I tried to get something out of them but it didn’t work. I didn’t give them anything and they didn’t give me much. It was more jokes, they are good boys. They were looking forward to playing at Celtic Park.”

Brendan Rodgers spoke of the improvements he has seen in Sviatchenko since the summer, compliments that are not just lip-service given that the Dane has been given the nod to partner the experienced Kolo Toure at the heart of defence for the Champions League games.

Certainly, Sviatchenko believes that he is playing the best football of his career.

Asked what he added since Rodgers had arrived at the club, Sviatchenko said: “Composure! And also with my possession, when we have to pass the ball, I’m getting better and better. I need to be better to perform at the highest level to go into the Danish national team and play regularly.

“What I am good at, is being a duel player. I win my duels. I think and try to intercept balls. To get better, it is always good to play games where you need to be at the highest level. I’m also getting older so I figure out what you’re good at and what your weakness is.”

The progress on the pitch has been attributed to Rodgers but the fact he is so settled off it has also had an effect on the player.

Sviatchenko’s partner, Anne Rudmose, has debuted for Celtic’s women’s team after the birth of the couple’s son, William, while his sister, Alexandra, is in line to begin work with the Celtic Foundation.

“My sister wanted to try something and my girlfriend and I said why don’t you come to Glasgow,” said Sviatchenko.”We know a lot of places and the city and it will be easy for them. They have been staying with us for the last two weeks and now they have found an apartment and Alexandra will join the Celtic Foundation and Emil, her partner, will work at Kember and Jones Bakery [coffee shop in West end].”

Kolo Toure’s experience was vital for Celtic when they took a point from their meeting with Manchester City in the previous game in Group C, and Sviatchenko has applauded the input the former Arsenal veteran has had on the Hoops backline.

“Kolo is as laid back as he looks but he’s a really funny guy as well,” said the Danish internationalist. “He’s calm but when he trains he’s there 100 per cent which is really inspirational.

“I’m progressing every week in every game but I’m still learning. I have Kolo by my side and I’ve also been playing with Jozo who hasn’t been playing that many games.

“So sometimes the role changes. It’s just good to have that because it shouldn’t be that I’m quiet when I play with Kolo. I won’t be quiet – I still want to be the dominant one.

“That’s what my playing style is about – being verbally present on the pitch.”

There is a stat currently doing the rounds on social media that Celtic have had more fans through the gate so far in 2016-17 (483,056) than any other club in Europe.

Certainly, they played a role in the game against Pep Guardiola’s side although it is effectively a two-way street with the players on the pitch requiring to give those in the stands something to shout about.

Sviatchenko, though, is hoping that they can contribute to making Celtic Park something of a fortress again as the Hoops look to lay siege to teams on home soil.

“We are not tourists in the tournament,” he said. “We believe we belong here but we need to work hard and see what we get out of it.

“We just need to get all the points we can and see where we are in the end.

“The atmosphere was very big for me in the City game but just imagine what it feels like to be on the other side.

“In those last couple of minutes the fans helped us when we really needed.

“If we can have that again then I am sure Monchengladbach will be really frightened.

“We need Celtic Park to be our fort. Teams need to be frightened to come here. In the City game you could see they were struggling - even though they are big stars.

“We’ll do our best to create that intensity again and when you bring in the fans it can be a good combination. Borussia might have looked at the City game but they will know this is a difficult place to come to anyway.

“If they think it will be easy they will be in for a surprise.”