Liverpool manager Benitez must make a strong case for defence

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Liverpool could go into Sunday's critical trip to Manchester City without veteran defender Sami Hyypia - the nightmare injury scenario the Spaniard has been dreading since Daniel Agger broke a metatarsal back in September.

Agger's injury left Benitez having to use Hyypia for an extended spell when he was only really supposed to provide cover for the established central-defensive pairing of Agger and Jamie Carragher.

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The 34-year-old Finn has been outstanding the last three months in shouldering a vastly greater workload than he or Benitez wanted but he twisted an ankle in the victory over Derby.

That leaves Benitez hoping Alvaro Arbeloa recovers from flu and that Agger can make a comeback soon.

"Sami has an ankle problem, it was a difficult situation. Arbeloa was out with flu, so we had no real cover. This could now be a real problem," said Benitez, who has been searching for cover in defence despite his fall-out with owners George Gillett and Tom Hicks over finances for January's transfer window.

To help speed up his comeback Agger has been training in boots specially designed to take pressure off the healed bone.

Apart from the Denmark international, Benitez's only other options are rookie defender Jack Hobbs or moving full-back Arbeloa inside.

"Daniel Agger is closer, he has been training this week. We will wait to see how Sami is but we can use Jack or we could push Agger to play, we will wait and see," said the manager.

"Agger is training with new boots, designed to help him play after the foot injury. We must wait to see how that develops.

"We had a problem for six, four, three months. That is the reason we were looking for options.

"Now you can see the problem and why we have been searching for re-enforcements, we have been playing with a big risk. And Jamie Carragher has four yellow cards so that just makes the problem more worrying.

"But Agger and Hobbs are both training and Arbeloa will recover from his bout of sickness. All that will be a big boost for us.

"We have tried to protect our centre-backs but it has been a long time playing with this risk.

"We would not have wanted to play Sami for this long in defence. Everyone was thinking that Sami would play some games with both Agger and Carra to give him rest.

"We have not been able to do that, and now we could have a real problem with his injury. But hopefully we can get Agger fit and on the pitch.

"It will be difficult against Manchester City with this problem. They are fighting at the top with us and Sunday's game is very important. We have to plan carefully."