Degryse believes Fellaini's game doesn't suit Martinez's system, nor the players at his disposal.
"In possession of Eden Hazard and Kevin De Bruyne, more than ever their play is dependent on rapid delivery," Degryse told HLN.
"If you have two defensive midfielders, they need good feet. In fact, one should be a sort of Pirlo. Axel Witsel can be like that, but I find him always timid and he doesn't push the game fast enough.
"With Fellaini I have greater doubts in this system. (Radja) Nainggolan would be a solution, because his application is pretty good."