London, Aug 8 (DPA) Liverpool completed the signing of Alberto Aquilani from Roma as manager Rafa Benitez moved quickly to replace Xabi Alonso after his move to Real Madrid.

The two clubs had already agreed a fee -- reported to be around 20 million pounds -- before Aquilani came through a medical and signed a five-year deal Friday evening.

The 25-year-old has not played since March because of an ankle injury and he is likely to miss the start of the season, with the club expecting him to be fit between four to eight weeks.

'He will continue his rehabilitation under the guidance of our medical team,' Liverpool said.

Aquilani joins full-back Glen Johnson as Liverpool's second significant signing of the summer, with Benitez spending around two-thirds of the 30 million pounds he received for Alonso to secure the services of Italy midfielder Aquilani.

'Alberto has a winning mentality and great experience in both Serie A and the Champions League,' Benitez said.