While the season ended in disappointment for Liverpool, taken as a whole, the campaign was one of immense progress for the 18-times champions of England and provides real optimism going forward under the long-term strategy of manager Brendan Rodgers.

Key to ensuring the club build on their success, both in the Premier League and Champions League nest season, will be their recruitment this summer. The demands of the Champions League mean that significant investment will be required. Rodgers relied on a small group of players this season and also largely utilized those that were already at the club when he arrived.

For all their progress, the work done by Liverpool’s “transfer committee” has had mixed success, at best, and has suggested that Rodgers may not always have been in total agreement with its conclusions. This summer the Liverpool boss will have to be given signings that he trusts to utilize on a regular basis.

Here are five players that could fit that requirement.

Adam Lallana (Southampton)

Lallana looks set to be Liverpool’s first signing of the summer, with a £20 million bid reported to have already been made. It is likely to cost Liverpool a few millions pounds more to eventually prize him away from Southampton, meaning that they will certainly be paying the familiar premium for English players. That is not to say that it would not be a good deal on Liverpool’s part. Lalllana has enjoyed a superb season on the South Coast, which has rightly been rewarded with a trip to Brazil for the World Cup. He has the intelligence and positional-flexibility on the pitch to fit nicely into a Rodgers team that requires players to adopt different positions, formations and tactics. Capable of playing anywhere along the line of three attacking midfielders, and potentially in a central midfield trio, the 26-year-old will provide a valuable, complimentary alternative to Philippe Coutinho and Raheem Sterling.

Cristian Tello (Barcelona)

If Lallana is signed then Rodgers may well look to spend the rest of his available funds on other areas. However, young Barcelona winger Tello could offer the threat of real pace on the left flank that Liverpool currently lack and that Victor Moses failed to provide during his loan spell. Liverpool’s two attacking signings from Spain last summer, Luis Alberto and Iago Aspas, have thus far failed to pay dividends, with the pair starting just five Premier League games between them. One or both could leave, meaning Liverpool would need to strengthen that area. There is no guarantee that Tello would be a success, either, and certainly is still inconsistent. But he has undoubted talent and, having been linked with him for so long, Liverpool could find that the 22-year-old is now resolved to leave Barcelona in order to get more regular first-team action.

Javier Mascherano (Barcelona)

If Liverpool do make an approach for Tello, they might be wise to also inquire as to the availability of Mascherano. The Argentina midfielder has been deployed at center-back, largely with success, since leaving Anfield for the Camp Nou in 2010. However, he has hinted that he could seek a move amid much upheaval expected at Barcelona this summer. And, according to Catalan publication Sport, the 29-year-old would be open to a return to Liverpool and potentially finishing his career there. If so, Liverpool would surely be negligent not to pursue a transfer. While Steven Gerrard has performed admirably as the deepest-lying midfielder, Liverpool could do with the option of a player more equipped without the ball, while still comfortable with it. In that regard, Mascherano would be an upgrade on Brazilian Lucas Leiva and, while too short to play at center-back in the Premier League on a regular basis, would offer the option to fill in on occasion.

Steven Caulker (Cardiff)

The disappointments at the end of the season for Liverpool only emphasized that strengthening their defense will be a priority in the transfer market this summer. The club actually signed three central defenders last summer, but none proved a resounding success. Portugal Under-21 international Tiago Ilori was sent out on loan to Granada and still has time to prove his qualities. The same cannot be said for Kolo Toure, who brought experience but also a penchant for committing ludicrous, costly errors. Mamadou Sakho was the big signing in the last close season, arriving for £18 million, yet he was restricted to 17 Premier League starts. It is believed that Rodgers will look to strengthen again with the capture of Cardiff defender Caulker, who he knows well from a loan spell at Swansea in the 2011-12 season. While he would not be a signing to wow fans, the 22-year-old England international would be a solid addition, who still has time to improve.

Alberto Moreno (Sevilla)

Liverpool were forced to play almost the entirety of the season without first-choice left-back Jose Enrique. Just how much of a blow this was is questionable, however, with Rodgers never quite seeming to be overly keen on the Spaniard and having brought in Aly Cissocko on loan to challenge him. As it was, the Valencia man was a disappointment, meaning young Jon Flanagan ended up stepping in on the opposite flank to his natural position and doing an admirable job. Still, it is likely that Rodgers will seek an upgrade on the position this summer. The club have been linked with Sevilla’s Moreno, who has been named in Spain’s provisional squad for the World Cup. He would represent an upgrade, although Liverpool could face stiff competition for the talented 21-year-old, with Chelsea thought to be keen.

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