Stevens worked with the Netherlands international for one season at Hamburg before the 29-year-old midfielder completed a move to La Liga outfit Real Madrid in 2008.
Van der Vaart has scored 28 goals in 76 appearances since his switch to White Hart Lane, but Stevens insists the Ajax youth graduate would be welcome at Schalke if the midfielder is looking to return to Germany.
“His qualities are unprecedented,” Stevens told Sky Sports.
“I would love to work with him again. We have contacts with his agent. Every day I speak to Horst Heldt [Schalke’s general manager] on the phone about our plans.
“There are rumours circulating that Rafael would return to Germany. But I have not heard from his mouth. I have not spoken with him and we’ll have to see after Euro 2012.
“He has a contract so we will have to pay a ransom. If Rafa really wants it, he is welcome.
“If that opportunity arises, and he looks forward to it, let him come.”
Meanwhile, Stevens also revealed his interest in free agent Kalou, who has also been linked with a move to Liverpool.
“Kalou is a Bosman player this summer,” he added.
“It’s obvious – there are many other clubs keen on him. Liverpool for example. But I know for sure he wants to move away from England. This could be our chance!”
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