Norwich City’s bright young things must wise up fast in the Premier League, warns Daniel Farke.

The City chief was unimpressed by what he saw in the first half of a 3-1 home defeat to Manchester United in both penalty boxes.

Captain Alex Tettey vented his frustration in the Norwegian media at what he labelled 'naive' defending, and Farke is on the same page. The City head coach is challenging his exciting talent to kick on after impressive senior breakthroughs on his watch.

"We will speak with the younger players because I was not overly happy," he said. "We started pretty well, we had the biggest first chance of the game from less than 18 yards, a shooting position without any pressure. You have to be convinced and focused in order to score and if the keeper produces a world class save then you take it. We cannot be happy to create a chance and not be greedy to use it.

"The same happened before the first goal. It wasn't even a real chance. A cheap cross, we get the first touch and then we seem surprised the opponent is also in the box. That is an assist from us.

"Our positioning on the second goal on the counter was a disaster, if I am honest.

"The biggest strength of United at the moment is pace and counter-attacks. Our positioning was horrendous in this scene. These are topics we have to speak about and be self-critical.

"That is what you get with young players and technical players."

Farke insists tough love is the only way forward for Norwich to compete against the cream.

"It is difficult to be angry with these lads. They are always willing to keep on going and they showed great character in the second half," he said. "They always show a great mentality so angry, no, but self-critical, yes.

"They invest so much but this was a day when you have to say as a young player you must develop a bit more and learn some lessons. That is why the best teams in the world don't play with a lot of teenagers.

"We were not physical enough. If you are not there and everything is not top class you have no chance as a newly promoted side.

"We brought some more physicality into the side at half-time, but if you want to be successful against Manchester United then you have to be switched on in the duels."