IT is a policy which has served Celtic well, and looks likely to do so again. Discovering young, raw gems and polishing them into diamonds is a familiar custom around the corridors of Lennoxtown.

Gary Hooper, Victor Wanyama and Adam Matthews are just some of the players in recent years that have been brought in for relatively low investment, only to leave, returning a handsome profit. Virgil van Dijk seems poised to be the next on the conveyor belt of talent that is drip-feeding footballers into the Barclays Premier League, with a move to Southampton the likely destination for the Dutch centre-half.

However, such a focus on recruiting relatively fresh-faced players with the aim of cashing in comes with risk attached. This was demonstrated perfectly on Tuesday, a night that Ronny Deila admitted took almost two days to shake out of his system.

The Celtic manager fielded a team against Malmo for the Champions League play-off second leg with an average age of just over 25 and at times they looked overawed by the magnitude of the task. The most galling factor was that when captain Scott Brown was struggling to impose himself, there was nobody with the experience or courage to take over and haul the side out of trouble.

It is a problem that has not escaped Deila’s attention, and is one he is keen to rectify ahead of a Europa League campaign that has thrown up a group filled with the tricky trio of Ajax, Fenerbahce and Molde. “It’s not a criticism. We have to build leaders into the group as well and Broony is a fantastic leader. But we need more than him, we can’t depend on one,” said the Celtic manager.

“We need more experience and players who take responsibility, but that will come. There’s a lot of prospects within the group who can be leaders, but that’s one of the tasks I need to build together with my staff.

“It’s a policy within the club that we want to bring in players we can develop and be worth more later. But we have to find a balance between experience and youth because you will have a lot of lambs with one shepherd. If you bring kids into the world, you also need parents and it’s the same on the pitch. Getting that balance is always important.”

The benefit of having an older head in your team to cope with such situations was confirmed by Celtic’s opponents on Tuesday night, when veteran striker Markus Rosenberg opened the scoring for the Swedes.

The 32-year-old was a key man for the team that can now look forward to a Champions League campaign against Real Madrid, PSG and Shakhtar Donetsk. This is his second stint at the club where he began his career, and it’s clear, at least to the Celtic manager, that the attachment he has to the Swedish champions played a big part in his return. It is a tactic the Norwegian is keen to employ himself.

Only this year there was an attempt to bring Darren Fletcher to Celtic using such persuasion. While it proved unsuccessful, it has not deterred Deila. “It’s a big challenge,” he said. “We have players, Darren Fletcher is one, who went to West Brom on three times the salary he could get at Celtic. We were talking to every player who has a connection to Celtic, with that type of experience.

“He [Rosenberg] is from Malmo. It’s about players from Celtic coming back and wanting to play for Celtic. Rosenberg would never come to Malmo if he wasn’t from there, if he was from Drammen, he would have gone to Stromsgodset.

“We have to look for experience as well and combine that with young talent. We can bring in players with experience but we don’t spend a lot of fees on that because you don’t get your money back.”

Deila was with his players at Lennoxtown for Friday’s Europa League draw that threw up certainly a more sexy set of fixtures for the club’s supporters to get excited about than Salzburg, Astra and Dinamo Zagreb managed last year. He insists the pain of not being part of the draw 24 hours earlier is now out of his system.

“It’s an exciting draw. There’s some big teams there and there will be some good games. It shows there’s a lot of quality in the Europa League. I don’t know where you get that from, that the boys are not excited by the Europa League. The players know it will be exciting.”