Jürgen Klopp may have only officially launched his Liverpool 2.0 this summer, but the construction of his upgraded model has been going on for some time.

It began first with the attack being slowly but gradually reformed. Then it was followed by the complete midfield overhaul last summer. And, last but not least, it will continue with the reshaping of the Reds' defense.

With Klopp's key stars in defense not getting any younger, it is clear that the Liverpool boss needs a refresh. Not only does he need a long-term replacement for Virgil van Dijk in the left-sided center-back position, but he also needs to find a long-term heir to Joël Matip's throne at Anfield. With the Cameroonian international's contract expiring at the end of the season and no extension in sight, it is entirely possible that he will be moving on to pastures new next summer.

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Replacing Matip will not be an easy task. He is a unique profile in the Liverpool squad. He may not necessarily be the fastest player on the pitch, but his reading and anticipation of the game are excellent. On top of that, he is also really comfortable in possession and relatively strong in the air as well.

Matip's rogue runs forward make him a key instigator in Liverpool attacks, too, especially when the opposition pulls back and plays a low defensive block. In those times, having someone like Matip bringing the ball forward and beating opposition players is vital for Liverpool.

One potential future candidate who may be a bit of a project for Liverpool but could be a relatively cheap option is 20-year-old Martin Vitik, who is showing some really encouraging signs of late. Over the last international break, he made his senior debut for the Czech Republic and impressed so much that he was named in Whoscored's Team of the Week alongside Dominik Szoboszlai.

Vitik, who plays for Sparta Prague, has long been highly regarded by the Czech side. At 20 years old, he has already played 87 games for the club's first team, and his senior debut for the national team has been a long time coming. His recent impressive performances in the Europa League have definitely helped his case, with Vitik scoring against Aris Limassol and then helping his side to a clean sheet against Rangers at home.

The reason why Vitik's profile should appeal to Liverpool is because of his reading of the game. He is an excellent defender who positions himself well. Like Matip, he is also a bit of a goal threat, having scored three goals already this season and, on top of that, he is very good at bringing the ball forward. Last season, as per Wyscout, he ranked in the top five center-backs in the league for progressive runs, averaging 1.77 per 90.

He is a player who would be available for a relatively cheap price, and while Vitik would be more of a project signing who will need time to adjust to the Premier League, given his impressive talent, he is worth taking a punt on.