England's Euro 2012 campaign has been blighted by injuries, with Chelsea defender Gary Cahill the latest of their players to be ruled out of the tournament after suffering a broken jaw in Saturday's 1-0 friendly win over Belgium at Wembley.
Standby defender Phil Jagielka had already been called up after Gareth Barry, as well as fellow central midfielder Frank Lampard, had been ruled out of the tournament earlier in the week.
But having left the 81-times capped Ferdinand, 33, out of his original squad "purely" for footballing reasons, Hodgson decided to bring in Martin Kelly as Cahill's replacement on Sunday even though the Liverpool player has just two minutes of international experience behind him after coming on as a substitute late in last week's friendly win away to Norway.
Ferdinand reacted to his ongoing international exile by asking his Twitter followers: "What reasons?????!!"
There had been concerns Ferdinand would not be able to get on with regular England central defensive colleague John Terry, who is in the squad, because of the Chelsea captain's court case next month over allegations he racially abused Ferdinand's younger brother, Anton, during a Premier League clash with QPR last October. Terry denies the charges.
Hodgson has always insisted Rio Ferdinand's omission is a football matter.
But, clearly, the centre-back and his camp are far from convinced and, given Kelly made just 12 appearances for Liverpool last season, they are unlikely to be alone in asking questions.
"Lampard, Terry, Barry, Gerrard; all ageing but they go to the tournament," Ferdinand's agent, Jamie Moralee, said Sunday. "Why is Rio different?
"To treat a player that has captained and served his country 81 times (in this manner) is nothing short of disgraceful. Total lack of respect from Hodgson and the FA (England's governing Football Association) as far as I am concerned."
England's injury situation is further complicated by the fact Terry suffered a hamstring strain against Belgium.
The FA said Terry had been given the "all-clear" Sunday but added he would be re-assessed on Tuesday.
Hodgson is next due to speak in public after England arrive at their Krakow base on Wednesday and now the FA must decide whether, in the intervening days, they respond to the Ferdinand camp's comments.