Liverpool have a big summer on the horizon. Head coach Arne Slot and sporting director and Richard Hughes will have been with the club for one year, so the time for action in the transfer market is finally upon them if they are to make this project truly their own.

Out of all the positions in Slot's system, the centre forward has been the one hardest to nail down with the options Jurgen Klopp left at Liverpool. To start it was Diogo Jota until injury hampered his progress, Darwin Nunez would have been expected to take over but has in actual fact made 16 starts, 33 total appearances, with a return of only six goals.

Luis Diaz seemed to be a revelation through the middle at first, though without so much as a big chance created - let alone a goal or assist - in his last 10 outings, his form is arguably not to be relied upon alone. Luckily none of this has not hampered a title charge though it must be admitted, it seems a problem that cannot extend into next season or beyond if further honours are going to be contested.

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As one of the Premier League's best current goalscorers, it therefore comes as no surprise to see Alexander Isak linked with a switch from Newcastle. Rumours suggests he is keen on Anfield and the Champions League football on offer there, though a £150m fee could prove to be a stumbling block.

But Liverpool have a negative net spend of -£17.4m for the term, according to Football Observatory, and three in line for an exit could help raise the necessary funds for Isak come to mind - the easiest being Caoimhin Kelleher.

Even though the 26-year-old himself has proven himself a worthy successor to Alisson Becker, last summer the Reds secured the future of the goalkeeping department with a £30m agreement to sign Giorgi Mamardashvili. The 24-year-old will move from Valencia ahead of next season.

Alisson is ahead of Kelleher in the pecking order and it remains to be seen how the upcoming switch-up is going to be handled. What is known is the Irishman's past expressions of desire to depart with this now the case, and a current Transfermarkt value of £18.3m would pocket the club a tidy sum, and that may actually be towards the lower end of the spectrum based on his performances when called upon.

Following that, the start of a revamp of the attacking department could see both Nunez and Diaz sold to make way for Isak.

As mentioned, both players' form under Slot can be questioned. The Uruguayan is reaching what should be his 'peak' years when his numbers in front of goal have regressed whilst the Colombian is reaching two years before the end of his contract, so realistically would be the time to cash in for the best possible price without forcing a renewal.

Throughout the recent January window, Nunez was reported to be of interest to Saudi Pro League clubs. Since he has joked about the allure of money from the Gulf state. With the latest word suggesting at least £64m could be recouped for the attacker that cost £85m and has afterwards failed to set the Premier League alight, how can that kind of money be turned away?

Diaz on the other hand has been of rumoured interest to Barcelona. The 28-year-old, according to reports in his homeland, could fetch £59m from the Spanish giants and with his contract shaping up the way it is against the current backdrop of form, it looks to be a potential avenue that could be explored.

Added to Kelleher's value, those sums would amount to a total £139.7m worth of player sales based on current estimates. That is without considering other fringe players under Slot's watch, but the club's cash in hand from this season's negative net spend would help take them over the line for the £150m reportedly demanded for Isak's move from Newcastle.

The Reds can only hope the Sweden international's stock does not continue to rise between now and the season's end. He has upcoming important dates against his 'suitors' at Anfield and Wembley Stadium in the calendar.