The Latics boss has said that he isn't looking to add a centre back, despite the recent injury suffered by Ivan Ramis.
Speaking after the draw with Fulham at the weekend, Martinez said: "We are in the January window and we are still looking for one player.
"I don't think we are going to look for a centre-half because we still have Antolin Alcaraz to come back from injury and Roman Golobart has done really well in the cup.
"I think we will have to cope with it internally, but we'll still try to add one more face before the window closes."
The Latics have been linked with a loan move for Atletico Madrid goalkeeper Joel to provide competition for Ali Al-Habsi.