Luis Diaz makes the difference after surprise arrival to revitalise formidable Liverpool attack

The Colombian has been a revelation since arriving in January from Porto to hand the Reds more options in the final third

Liverpool's Colombian midfielder Luis Diaz celebrates after scoring (AFP via Getty Images)

It’s not so much a question of how you improve upon arguably the best group of attacking players in European football – but why, when you already know that the four of Mohamed Salah, Sadio Mané, Roberto Firmino and Diogo Jota will not go into three, is it absolutely necessary to spend £37m on a fifth?

There were, in reality, quite a few good reasons why it made sense for Liverpool to sign Luis Diaz when they did. Most of all, there was the threat of being gazumped rather than doing the gazumping, but the age profiles and contractual situations of Salah, Mane and Firmino made another forward a necessity anyway, sooner or later at least. It’s not as if any supporters were turning their nose up at the sudden news of Diaz’s arrival either.

Nevertheless, it left Jurgen Klopp with a slightly top-heavy set of resources and a challenge to give all of his forward options the minutes that their prodigious talents deserve. You can have too much of a good thing, they say. Then again, maybe you can’t.

Signing Diaz early when in other circumstances a move could have been postponed until the summer is proving to be nothing like overkill, especially not after his crucial role in killing off a Champions League first leg that had briefly threatened to get away from him and his new teammates.

Diaz not only restored a comfortable two-goal cushion with his late strike in the 3-1 victory, but he assisted the second, reading Trent Alexander-Arnold’s masterful crossfield pass brilliantly to cushion it across the face of goal with a diving header for an easy tap-in. El Quinto Beatle is very much part of the band.

Diaz has already made the difference for Liverpool (Getty)

He is needed, too. It was noticeable at the Estadio da Luz that after Darwin Nunez pulled Benfica back into the tie and the home crowd began to sense an equaliser, Klopp made three changes in one fell swoop and sacrificed two of his front three. Salah and Mane both departed. Diaz was the only one in the attack to survive.

Sunday’s trip to Manchester City had to be playing on Klopp’s mind and it would not be entirely surprising if both substituted players started at the Etihad while Diaz is rested after a 90-minute workout in Lisbon. The patchier-than-usual form of Salah and Mane cannot be taken out of the equation either, though.

Mane’s goal was his first in five appearances, second in seven and fifth since returning from the Africa Cup of Nations two months ago. That is not a poor record but some way off his usual standards. The same is true of Salah, who also has only five over the same period, three of them coming from the spot. It is now eight games since his last non-penalty goal.

Liverpool have been safeguarded themselves against fatigue from Mane and Salah (EPA)

There was plenty of speculation at the start of the season over how Liverpool would be affected by Salah and Mane’s participation at Afcon, less so when it emerged they would only miss two or three Premier League games at most. Salah was away for a month but only sat out of wins over Brentford and at Crystal Palace, then came straight back in.

In a way though, that scheduling quirk only made Salah and Mane’s respective seasons longer, increasing the number of intense and demanding games rather than swapping several out. And that was before Senegal and Egypt drew each other in a two-legged World Cup play-off.

Mane has played 47 games for club and country this season. Salah has played 52. It would be understandable if exertions earlier in the season were starting to catch up with them, or if both players are beginning to feel the strain of recent months, as Klopp suggests they are.

“It’s a tough period. Both boys came back from Africa and it’s really not easy,” he said, of those recent World Cup play-offs. “A massive pressure on both their shoulders, both had to sort it for their countries, their managers played a part in that as well, to put it on them. Now it needs a bit of time to settle, that is all.

“It was an important game for Mo and Sadio tonight, one could score, one unfortunately not but everything will be fine.”

Jurgen Klopp is relaxed about the form of Mohamed Salah and Sadio Mane (AFP/Getty)

It was not as though the pattern of the game presented an opportunity to rest both of them either, with Benfica pushing for an equaliser at the time of their withdrawal. Klopp described the leg and the tie as “open”, at that point and even after Diaz’s goal and the final whistle. The changes were made out of necessity rather than luxury.

“Hopefully at one point this discussion will stop about having an advantage with five substitutes,” Klopp added. “It’s April, we have already 49 club games plus the games the boys played for their countries ... The boys will dig deep but the more we have the chance to share this intensity, the better for the players and the better for the game.”

In those circumstances, in this climate with a post-Covid schedule trying to play catch up, perhaps stockpiling talent is a perfectly sensible idea after all. The signing of Diaz came by surprise, perhaps six months sooner than normally would be necessary, but he could make all the difference to them getting over the finish line.