Mino Raiola steered Erling Braut Haaland away from joining Manchester United in January 2020, according to Borussia Dortmund chief executive Hans-Joachim Watzke.
Man United were strongly linked with the Norwegian during his time at Red Bull Salzburg, but the striker ultimately joined Dortmund from the Austrian club.
The 21-year-old has scored 70 goals in 69 appearances for BVB in all competitions, and a number of clubs, including the Red Devils, are expected to compete for his signature next summer.
According to Watzke, Ole Gunnar Solskjaer's side made a 'better offer' for Haaland, but his agent Raiola believed that the Norwegian would be "better off" in Germany.
"The offer from Manchester United was better," Watzke told Sport1 . "However Mino Raiola realised that Erling is better off with us.
"People notice that gifted people make a breakthrough with us the quickest. That is a resounding argument for the players, the parents of the players and the advisors. We have no inhibitions about letting 17-year-olds play."
Haaland has scored 13 times in 10 appearances for Dortmund this season but is expected to be on the sidelines until next year due to a hip flexor problem.
