The January transfer window may have got off to a slow start for Norwich City but supporters are sure of the key area for the Canaries to invest in once the merry-go-round starts to spin.

City boss Alex Neil has already reiterated that any incomings will be dependant on money generated by sales this month, as the club continues to adjust to the financial realities of life outside the Premier League world of ridiculous riches.

At November's AGM technical director Ricky Martin admitted that some turnover of the squad will be needed, with a desire to lower the squad's annual average age and moving on some out-of-favour players discussed, as it was revealed that he would be taking on added responsibilities for player recruitment.

So far the only arrival has been that of Icelandic 16-year-old Agust Hlynsson, clearly a signing made with an eye on the future, and the only outgoing has been young left-back Harry Toffolo returning to Scunthorpe on loan.

Any signings that Neil, Martin and chief executive Jez Moxey went to make appear to be waiting on the potential exits of players including Robbie Brady, Sergi Canos, Michael Turner and Kyle Lafferty.

With a third of the transfer window already gone, fans are having to wait patiently to see if City are able to boost their play-off hopes with new signings, so we asked which position is the main priority to be strengthened.

Perhaps unsurprisingly, as only four teams have conceded more goals in the opening 25 games of the Championship season, central defence was the overwhelming winner of our poll on pinkun.com.

Neil's team have let in 37 goals in those 25 matches and sit in ninth place in the table ahead of Saturday's trip to Rotherham.

The bottom-of-the-table Millers have the worst defensive record with 55 goals conceded. Nottingham Forest (45 conceded) in 20th, Blackburn (40) in 22nd and Cardiff in 19th are the only other teams to have conceded more than City and Barnsley, who are tied on 37.

It is not a record reflective of a team hoping to be promoted and makes clear where the problem lies – with only three teams in the league having scored more goals than the Canaries' 41.

That could mean an exit for one of the current centre-backs but who is in line for the chop?

An average of 1.8 goals have been conceded in matches when Seb Bassong has been playing (14 in eight league games) – making him the worst defender statistically.

Timm Klose (23 in 17) and Ryan Bennett (29 in 21) both average 1.6 conceded when on the pitch so far and Russell Martin 1.6, although some of his games have been played at right-back.

John Ruddy's return in goal in the last 10 games has steadied the ship, with nine conceded in nine games and clean sheets in the last two matches as Klose and Martin have returned at centre-back – will they soon have fresh competition though?

• Poll results correct as of 5pm yesterday, when over 1,000 votes had been cast. See the latest results and cast your vote in the poll above.