Carragher wrote in the Daily Mail: "He arrives on Merseyside with a solid reputation and it was interesting to hear that Ian Ayre, Liverpool's managing director, described him as 'a marquee signing' - when you spend £18million on someone, you would expect they will play.
"So it will be fascinating to see how Brendan fits Sakho in. He is a left-sided central defender but Liverpool already have a very good one of those in Daniel Agger, who has succeeded me as vice-captain.
"In my experience, you can play two right-footed central defenders as a partnership - that was the case when Sami Hyypia and I played alongside each other - but I have never seen a team line up with two left-footed central defenders as a partnership."
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