The DW Stadium club have greater concerns over forward Maloney's groin strain and are hopeful defender Ramis' hamstring problem is not too serious.
But Wigan were already without Ben Watson, captain Gary Caldwell, Ryo Miyaichi, Albert Crusat and Antolin Alcaraz against Reading in what is a serious injury crisis.
And so having to substitute Maloney and Ramis was the last thing they needed ahead of hosting defending Premier League champions Manchester City on Wednesday.
Martinez said: "Shaun's injury is worse than Ivan's. He has picked up a groin strain and, although we'll assess him, it looks as though he'll be out for a while.
"With Ivan's injury, we managed to catch it just in time before it got worse. He felt a twinge in his hamstring and we'll assess him to see how long he'll be out for."