The Australia international has instructed the two youngsters to carefully consider their futures
The two players are considered among European football’s shining young hopes and both have been subject to overtures from some of the game’s leading sides ahead of their return to top-flight action on Saturday against Schalke, following an unscheduled break due to the coronavirus pandemic.
Sancho, in particular, has been in the spotlight as the summer approaches, with the England international winger having dramatically improved over the course of his near three-year stay in the Bundesliga.
“There’s absolutely no reason why any of them should leave,” he said.
“For example, Robert Lewandowski left Dortmund at 24 if I’m correct – 24, 25 – and he was absolutely smashing it at Dortmund and then he’s been smashing it at Bayern.
“He went there as an absolute starting striker, there was no doubt, the same as Ilkay Gundogan. He came at 21, left at 24, 25, went to Man City and is killing it.
“There is no rush for these guys to leave when they’ve got the perfect situation. Haaland could go 10 games without scoring a goal and the fans would celebrate him like there’s no tomorrow.
“It’s the perfect scenario where he’s got the blessing of the support of the whole club, the whole city, and it’s sort of ingrained in Dortmund’s tradition to have good, young, hungry players – and when the time is right maybe they’ll leave.
“But I don’t see why they should when they’ll be playing Champions League [football] regularly. Hopefully going into the latter stages of the Champions League, pushing for the Bundesliga title and playing for their national teams…
“There’s only a handful of clubs that are actually bigger than Borussia Dortmund.”