When Jude Bellingham came through at Birmingham City at the age of 16, you thought 'wow'.

If he has another 10 years of development, he is still only 27. That in itself is really scary. Is he the finished product? No. But for Borussia Dortmund, who signed him in July, it's such a good investment.

Dortmund bought him because they can improve him and then his value will shoot through the roof. He's a top talent.

You always want your local kids to do really well. When you saw he was a talent and he could hold his own, that got everybody more excited at Birmingham.

He was never physically dominated and he was always technically very good. His profile as a centre midfielder and as an all-round midfielder attracted a lot of interest.

Why he reminds me of a young Vieira

What I like about Bellingham is what he does when he gets the ball on the run. He is so powerful when he's running from deep. His goal on his Borussia Dortmund debut - in the cup victory over Duisburg - was about getting himself into the box. That's where I think his strength is.

Dortmund manager Lucien Favre said Bellingham was versatile and can play in any position, which was why he was excited by him.

But I don't think the holding midfield role - where he featured a lot for Birmingham - is where he is strongest.

He reminds me of a young Patrick Vieira, the former Arsenal and France midfielder, with how he tackles and plays from box to box. He's fit, quick, powerful and he's shown he can score goals. I like him more when he is running from deep and getting into the box - like Frank Lampard used to do for England.

It's a big responsibility for a young player to be a holding midfielder. I watched him play in the England youth teams when the opposition held more of a low block and he was behind the ball a lot. I don't think that suited him.

His finishing can continue to improve if he wants to be this box-to-box player and if he is going to play that holding midfield role then the tempo of his passing becomes even more important.

He has a good mentality though, all the physical attributes and technically he's good. I like the fact that at Birmingham, he always wanted the ball. He never hid from it. And at 17, the world is his oyster.

Why joining Dortmund made sense

The key thing is that Bellingham had to play regularly. There was no good going from the Championship to sitting on someone's bench. By going to Germany, I think he will play regular football with top players.

It was a similar thing with Jadon Sancho. He wasn't getting game time at Manchester City so went to Dortmund and now he's touted all over the world.

You have to remember Bellingham was linked with some top clubs for such a long time and it didn't look like it fazed him. He still conducted himself in a really good manner off the pitch.

For someone so young - getting linked with Manchester United, Arsenal or Dortmund - he could easily have lost focus with all the attention. He came in, did his job and was really professional and the Birmingham fans liked him because of that.

Not being in England now is a good way to get away from the media a little bit. The Premier League is a different beast. He can go to Germany, learn his trade at a massive football club and play a lot. His development will be brilliant.

Going to a different country and potentially learning a different language can help him really grow and mature. When I played abroad for Chicago Red Stars, it changed my whole perspective of things as a person and a player.

If he went to Manchester United, would he get the same game time that he likely will at Dortmund? I don't think so. Footballers want to play football.

At the age he is now, he has to play, because you develop so much during this period. I would love to see him playing centre midfield for England one day but for now, he just needs to keep learning.

Karen Carney was speaking to BBC Sport's Emma Sanders.