The French striker quickly became one of the most sought-after talents in European football after making his first-team debut for Monaco in 2015 with a whole host of top clubs expressing an interest in the Frenchman.
Talking to theKicker
, former Dortmund scout revealed Borussia Dortmund almost signed Kylian Mbappe for free in 2016. He said: "It was a real shame that we couldn't get Kylian in.
"Kylian Mbappe was [available] free of charge at a certain point and there were many suitors. But we had no chance of winning that [race].
"If you had been able to steal Mbappe from Monaco for free at the time, it would of course have been a mega deal."
Mbappe will be back in action for PSG when they face Lille on April 3.