The Reds have kept only two clean sheets against top-flight opposition since mid-December and individual errors have contributed to that disappointing tally.
Kolo Toure has been responsible for two mistakes in three matches, gifting an equaliser to West Brom and then scoring an own goal against Fulham in midweek and his place is most under threat from Agger's return to the squad after missing six matches with a calf problem - a spell in which they kept just one clean sheet.
But while the purists may rejoice at the return of Liverpool's only genuine ball-playing centre-half - whose ability fits perfectly with Rodgers' insistence of building from the back - the manager stressed the most important thing about a defender was being able to do his primary job properly.
"I like defenders to defend first," he said ahead of Sunday's FA Cup fifth-round tie at Arsenal, the team they smashed 5-1 in the league at Anfield last weekend.
"Everyone talks about ball-playing centre-halves but you have to be able to defend and be able to cope with that first.
"Obviously if you have the qualities then we want you to play because it is important how we build our game and there is no doubt Daniel Agger is an outstanding footballer."
While Liverpool have dragged themselves into the Premier League title race, sitting just four points off the top in fourth place, Rodgers insists that will not affect their cup preparations.
In fact, he believes Arsenal's pending Champions League clash at home to Bayern Munich next week may have more bearing on the fixture.
"We want to win the FA Cup, that's our objective," he added.
"We've got no midweek game so we can go as strong as we wish to go.
"It's probably different for Arsenal, who have a massive game after ourselves in the Champions League, so they may have to look at it differently. We won't need to rest anybody.
"We want to do it for the club. Since I've been here we have changed the squad around in order to try and help us in the league.
"When I have made too many changes we haven't been good enough and that's seen us go out of tournaments earlier than I would want.
"This year we wanted to do well in the cup competitions - hence the reason why we've been strong.
"We want to get to Wembley, not for the semi-final, but for the final.
If we're there for the final, then it gives us a chance to win it."
Rodgers believes their league form, which has seen them drop just four points in seven matches since the turn of the year, stands them in good stead for a trip to the Emirates.
They were boosted by their last-minute win at Fulham in midweek where captain Steven Gerrard set up one goal and scored the winning penalty as the Reds twice came from behind for victory.
"That was a truly a world-class player," he said.
"There are a number of world-class players when they are 2-0 up in the game but you see world-class whenever you are down in the game.
"His pass (for Daniel Sturridge's goal, Liverpool's first equaliser) and his composure at the end showed the team is full of confidence.
"The result the other night gave us great confidence because we weren't at our best in terms of what we were against Arsenal but we still made 650-odd passes in the game.
"We came from behind twice and the calmness showed in the build-up to the penalty.
"We kept probing and passing, trying to find the space and not lumping it into the box playing panic football.
"That was pleasing with the calm nature we got the winner."