Liverpool have already added considerably to their midfield and attack this summer, with the view to building on the season they’ve just had and needing to replace, indirectly, the production of Luis Suarez.

But the club are in need of improving their defence, which caused a large number of problems throughout the course of last season. The loss to Aston Villa and draw to Crystal Palace stand out as particularly worrying games and examples of the deficiencies at the back.

But Brendan Rodgers clearly has the backing of the club’s hierarchy this summer. And with attacking signings already made, here are four centre-backs who would improve Liverpool’s fortunes on the pitch...

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Click on Federico Fazio to start the gallery

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Dejan Lovren

Liverpool are said to be close to landing Dejan Lovren from Southampton for a fee of £16 million. The Croatian would represent a good step up in quality from the centre-back options currently available at Anfield.

After a disappointing end to his time at Lyon, Lovren resurrected his career in English football and stood out as one of the best defenders in the league last season. At 25, Lovren has a lot to offer Liverpool, who are in need of stability at the heart of their defence.

£16 million would certainly have been a huge fee to ask for the Croatian, but a year on from his move to English football, he certainly warrants the profit Southampton are set make.

Inigo Martinez

Inigo Martinez is a player who could really thrive at Anfield under Brendan Rodgers, who has a good recent record of developing young players.

Inigo is known for his courage around his penalty area, but also for his high technical standard. His ability to play the ball out from the back would suit Rodgers’ game at Liverpool.

Real Sociedad will want to keep their defender, with Antoine Griezmann likely to be the second of two big departures at the club this summer.

But for the right money, Sociedad could be tempted to part company with the talented Spanish U21 international.

Hector Moreno

As expected, Hector Moreno had a very good World Cup with Mexico this summer, adding to the interested in him from his excellent displays with Espanyol in La Liga.

The centre-back has already been tipped for a move away the Catalan club, and despite his injury picked up this summer in Brazil, he’d represent a very good addition for many clubs across Europe.

Liverpool would instantly see their defensive department upgraded with the signing of Moreno, who possesses the strength and tenacity to be a hit in the Premier League.

Federico Fazio

Federico Fazio had a good season with Sevilla, helping them to winning another Europa League title. The giant centre-back has managed to turn around his game of late after being consistently error-prone, and has reportedly alerted clubs outside of Spain.

Fazio isn’t the most mobile but does well in aerial duels and has improved his reading of the game. Sevilla have already seen off one of their key players this summer in Ivan Rakitic and will be reluctant to lose another. But Fazio would represent a good addition at Anfield, especially one that played such a big part in losing out on the league title last season.