Northampton boss Gary Johnson is considering bringing in a defender on loan.
With Byron Webster already a long-term absentee, Seth Nana Ofori-Twumasi now has a knee injury that Johnson believes could take months to heal.
"It's disappointing for him and leaves us a bit short," said Johnson. "We might look at a loan."
He added: "We've just about got enough cover but we don't want to get caught out.
"I feel sorry for Nana, he's such an enthusiastic lad and he's going to be a top player.
"I would say he's going to be out for months, but hopefully he'll recover quickly."