Antenucci, Giuseppe Bellusci, Dario Del Fabro, Silvestri, Souleymane Doukara and Edgar Cani declared themselves injured on Friday, stunning head coach Neil Redfearn, who was forced to change his plans for his side's trip to the Valley on Saturday.
A number of Leeds fans believe the withdrawal of the six players, all signings from Italian clubs and five of the six brought in by banned president Massimo Cellino, has more to it than meets the eye.
And Claudio has opted to defend Marco, arguing that aside from his son and Antenucci, the other players involved have "made a stupid protest."
The goalkeeper's father was quoted as having said on Facebook by BBC Radio Leeds: "[Marco] does not know if he can train this week.
"[He] is really sorry the fans have become suspicious, he tried to explain, but I'm not sure they understood.
"A part [from] Marco also Antenucci is really injured, the other[s] have done, for what I know, a stupid protest."
Claudio also insists that his son is annoyed at having been dragged into a situation which is affecting his reputation with the club's fans, after the goalkeeper worked hard to establish himself in the eyes of the supporters.
"He is furious with those people because he took the whole season to make his name through the fans and now he is risking to spoil the relationship with them and with the environment."
Leeds owner Massimo Cellino has insisted that he did not tell the six players involved to go in strike while the club have issued a statement confirming all reported injuries are genuine.
Nevertheless, a number of fans appear to have now lost faith with the club's ownership amid a run which has seen the last five consecutive games lost and the position of head coach Redfearn undermined.
Without the injured six players, Leeds lost 2-1 away at Charlton.