The Argentine midfielder has failed to reproduce the form which saw les Parisiens splash out a reported 40 million euros to take him from Palermo in August 2011 and the Rosanero president believes the problem is a very obvious one.
"Why is he having trouble? Playing with Ibrahimovic is not easy," he told Corriere dello Sport.
His lack of form has prompted speculation that the 23-year-old come make a swift return to Serie A, where he enjoyed two fruitful seasons, and Zamparini revealed how Inter were keen on securing his signature prior to his move to France.
"[Massimo] Moratti was interested in Pastore before I sold him to Paris Saint-Germain and [Marco] Branca had spoken with my sporting director," he added.
"Then came the offer from Leonardo and Inter could not compete with those numbers."
A move back to Italy would appear premature for the time being, but that has not stopped the 71-year-old from dreaming of bringing Pastore back to the Stadio Renzo Barbera.
"If Pastore was to return to Italy I would be delighted. Javier still loves Palermo and the Saturday after our victory in the derby against Catania he congratulated many of his former teammates."
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