Evans said: "He could be the final piece in the jigsaw. Liverpool have been there or thereabouts over recent seasons and Harry will now give them that little bit extra.
"We have to beat the so called lesser teams at home more often - and we have to beat them convincingly. Harry's ability will be a great asset in that department.
"Last year was our worst for a while in terms of challenging Arsenal and Manchester United but this is a great signing for us."