Liverpool manager Brendan Rodgers says a lack of continuity in selection following the departure of Jamie Carragher is the reason behind the club's disappointing defensive record this season.
The Reds began the campaign with three successive clean sheets but have conceded 16 goals in their subsequent 10 league games, including six in their previous two away matches.
After keeping pace with Arsenal in the early months of the season, Liverpool's defensive troubles has contributed to them falling six points behind the Premier League leaders, while both Chelsea and Manchester City have leapfrogged them in the table.
Rodgers signed four defenders in the summer including centre-back pair Kolo Toure and Mamadou Sakho following the retirement of Jamie Carragher, while Martin Skrtel and Daniel Agger has also been involved this term.
And the Liverpool boss admits with his sweeping defensive changes yet to take effect, a lack of consistency in selection is hurting the club's Champions League challenge.
"It's probably the first job I have been in where there have been lots of areas I have been happy and settled in but central defence is an important area," Rodgers told the Liverpool Echo.
"It's something I need to look at in order to get that consistency we had in the second half of the season with Jamie Carragher.
"There has been lots of change - and some of that has been down to me - knowing every game is an absolute cup final for us. If I feel I have need to change it going into a game to get a result, then I will do.
"But of course, I also need to look at it from the coaching perspective as well, that a little run in the team might breed the consistency even though we have had to change a number of positions."
Liverpool face Norwich City at Anfield where they have only conceded three times in the league this season before the visit of West Ham United; two decent opportunities to resume their top four challenge.