With Darwin Nunez set to be unveiled as a Liverpool player on Tuesday, there is one important question hanging over his signing.

Is the £80m the club will potentially spend on his transfer an expensive remedy to a careless mistake in allowing Sadio Mane to get close to the end of his contract without agreeing an extension…or is it a masterstroke?

There is a fascinating dynamic when a club as big as Liverpool allows one of their best players - Mane is an all time Liverpool great surely - to leave, and then spends massively on his replacement.

On the surface, it could look a little careless. Mane, after all, was the team’s best player in the final third of last season, a player who seemed at the peak of his powers as one of the best in the world right now.

Yet he is allowed to go to a direct European rival, for a transfer fee less than half what the club must pay for Nunez, who will undoubtedly operate in the same positions, so a natural replacement.

Some would argue it is not the best management of contracts, that Liverpool got it wrong in allowing the Senegal forward to get so close to the end of his current deal, when he still has plenty to give in his career.

Yet there is a counter argument - which the club themselves believe to be the case - that the signing of Nunez is an important stage in the evolution of Liverpool Football Club back towards the summit of world football.

Perhaps the most pertinent point surrounding the two transfers, is that they are both done on Liverpool’s terms. If there was an overwhelming will to keep Mane, then he would have been retained. Nunez has been signed, because the club, weighing up the evidence, believes it to be the best solution, not a knee jerk reaction.

Mane is 30, and even if he retains a remarkable fitness, there is no doubt he will decline over the coming years of any new contract he signs.

Which makes that a huge contract for him personally, the biggest he will sign in his football career. Looking at the numbers, Mane was asking for close to £400,000 a week for a four-year deal to stay with Liverpool. That would work out at a total, including bonuses, of around £83m. A staggering amount, but similar to the likes of Kevin De Bruyne, David De Gea and Cristiano Ronaldo in the Premier League.

Bayern Munich are reported to be close to agreeing a three-year deal at around £360,000 per week. Which equates to £56m over the course of the contract. Whilst figures for Darwin Nunez are not yet confirmed by Liverpool, it has been reported in Portugal he will earn €6m a season NET.

That, by calculation, would entail a salary of around £160,000 -£180,000 a week, depending on his tax situation. Which equates, roughly, to around half what Mane will be earning. That would mean over three years, Liverpool will save around £30m on wages alone, by selling Mane and signing Nunez.

Add in the £40m they want from Bayern Munich from Mane - and seem increasingly likely to get as negotiations come close to a conclusion, and that is £70m in total. Which is, by any calculation, a financially savvy move.

Given Nunez’s fee will be £65m down, and another possible £18m in additional fees based on performance related targets, that means IF he is a success, Liverpool would pay - on those figures - around £13m to replace Mane with the Uruguay international.

While there are no guarantees in football, it makes sense from a logistical point of view. In three years time, Mane will be past his 33rd birthday. Nunez will be 25.

In a footballing sense, it is still a huge risk, because there are no guarantees the Uruguayan can translate his obvious promise into genuine quality…while Mane CAN guarantee that, as his form in recent months proves. Yet for how long? Even three years is quite a big ask for a player who has been pushed to the limit by an insane football schedule over the past few years. Mane is never injured, but can that continue in his 30s?

For Liverpool, there is an acceptance it is a risk…but it is a calculated gamble. For two reasons: One is their faith in the analytics they now run on all new signings, which are just about as sophisticated as you can get in modern football. They know Nunez’s strengths and weaknesses, they know where he can improve, where gains can be made. Which brings us on to the second reason for their faith.

In Jurgen Klopp, they have a manager who has displayed a world class ability to develop players, one matched perhaps only by Pep Guardiola and Carlo Ancelotti in the current generation of coaches.

So even if Nunez is raw, they have a manager who can swiftly develop him into a more rounded talent, who can take his promise and deliver the finished article. Just as he did with Mane, and with Mo Salah…and just about every Liverpool player.

Nunez could be a more natural finisher than Mane too, which would be important for a team who struggled to convert dominance in finals this season into goals. They didn’t score in all three finals they played last season, despite producing 76 shots in those games.

The Champions League final was the most painful of the experiences. They should have beaten an average Madrid side, no doubt. And there is a strong argument to be made, with Mo Salah slightly out of sorts, a natural finisher would have made all the difference.

They will miss Mane’s magic, no doubt. But from a financial point of view, the deals make perfect sense. They have maintained a wage structure which doesn’t leave them open to big demands from all their star players (a nightmare situation Manchester United have suffered from in recent years).