PETER JACKSON admits he could be forced into a signing if Town's defensive problems continue.
The Galpharm chief has brought in only three new players since winning promotion and still has power to add to his squad.
Chris Brandon, Junior Mendes and Akpo Sodje have all played their part in establishing Town as play-off contenders this term, while Paul Rachubka's loan return in goal could yet become permanent.
Jackson is reluctant to move further in the transfer market but might act if Town's push for the top six looks like stalling in the next few weeks.
"I'm really happy with the squad and when they are all fit and playing to their full ability, I've no problems whatsoever," said Jackson.
"I firmly believe we've got good ability and cover in all areas, so any signing will have to be absolutely right for our circumstances.
"If we hit a spell where we're not conceding goals or creating chances then you tend to edge towards thinking about a striker or midfielder, but then the niggling problem we've got at the moment is conceding stupid goals.
"Nine in the last two away games is not a pretty statistic.
"If that carries on then I might have to look at shipping in a defender, but we'll wait and see what happens because we are working very hard on preventing mistakes at the back and we've got one or two lads of our own waiting for a chance."
Those include the likes of John McCombe and Nat Brown, while Efe Sodje will return from suspension in December and Nathan Clarke's brother Tom is making rapid progress in the Youth team, who visit Boston in the Cup on Tuesday (7.00).
While the fringe players are eager to step up, Jackson insists he's running a happy ship.
"I've got 22 lads in my senior squad and while some people might think it's hard to maintain team spirit, I can guarantee the fans not one of the 22 wants to leave this club," added Jackson.
"It's rare you get so many players who get on together, no-one ever grumbles or comes knocking on my door and they all work really hard. I'm proud of them and they know I believe in their ability."
Last night, Cardiff City lost 1-0 to Preston in the Championship while in League II, Northampton drew 1-1 with Chester.