Few years ago I did 30m in 3.7 seconds. Whether that makes me quicker than [Usain] Bolt, I don't know! We all know Usain is the best.

Last season I scored 27 goals but still lost out against Robert Lewandowski. This season has started very well for me, but again I have some tough opponents, most notably with Anthony Modeste from FC Koln. I texted him the other day: "Keep calm, my friend." I am happy for him to be so successful. And in a certain way it even helps me. The better the other strikers are, the more I have to work to be to be ahead of them.

The moment my name was called [Africa's Footballer of the Year] was truly overwhelming and I was about to scream with joy.

Speed is a part of me. I think I was born with that, and nowadays a fast player, I need a fast car, too.

There are a lot of things to like about [Borussia Dortmund's fans] and the city of Dortmund as a whole.I like their honesty. And I like that my family and I can feel safe here. I don' t have to worry at all about my safety and their and my own safety. Believe me, in other countries I have made different experiences in that regard. All of this, too, has led to my decision to extend my contract until 2020, and I can imagine staying even longer.

We have our ambitions [in Dortmund Borussia], and of course I would love to win some titles after some years of finishing second or losing finals.

I always set myself new goals. I always want to do better than I did in the past. I always want to achieve things I never achieved before.