Ghoulam is currently working his way back from knee surgery, having suffered a setback in training earlier this month. His operation had been held in November.
Ferrari, who negotiated Ghoulam's move from St Etienne to Napoli almost four years ago, is in no doubt about the 27 year-old's quality. The Italian agent, having recognised his potential, placed Ghoulam at Napoli for a knockdown €340,000.
"Ghoulam has been very unlucky with his injury, that's all," he told Tribalfootball.com, arguing the defender is among the best left-backs in the world.
"Probably he is the best left-back in Europe alongside Marcelo (of Real Madrid), right now. Surely every big club would be keen on him..."