Trailing 2-0 at the break and all at sea at the Estadio de la Ceramica on Tuesday evening, Liverpool boss Jurgen Klopp summoned Luis Diaz from the bench in a bid to lift his side.
Villarreal's dream first 45 minutes, inside a cauldron of noise on home turf for the Yellow Submarine, had Unai Emery's men looking like they would be the ones to make the Champions League final in Paris later this month.
They had Liverpool on the ropes and the concerning nature of the Reds' performance in that first half had plenty fearing the very worst.
A lack of energy and invention, a hallmark of this most remarkable of Liverpool sides, was missing for the first 45 minutes in Spain until Diaz stepped off the bench to deliver a dagger to the heart of Villarreal as he lit a fire underneath the Reds in the second half, playing a key role in turning the tie on its head and igniting the teammates around him.
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It seems crazy to think that Diaz has been a part of this Liverpool team for just four months. His impact has been enormous, and in terms of the immediacy of it and how important it has been at crucial times for Liverpool already, it is hard to think of another January signing who has had such an immediate impact, one that has gone a long way to paying off the £49m tag that is on his head. Virgil van Dijk and Luis Suarez were both transformational January signings for Liverpool, but in terms of hitting the ground running and making an instant impact that has been so vital on the biggest stage, it's hard to look beyond Diaz.
That £49m, which will be the total outlay should all objectives and clauses written into the deal be realised, is already looking like a masterstroke. Liverpool have long been lauded for their ability to sign the right players at the right time and for the right price, and the foundations that Fenway Sports Group were so keen to lay when they arrived have been built upon, with Klopp being the perfect figure to steer the vehicle that so much unseen work through a large network of people behind the scenes at Anfield helped to build.
Diaz's 45-minutes last night was enough to see him given the accolade of Player of the Match. Liverpool may have got the result that they needed without his help, but given that first 45 minutes it is hard to see a positive outcome without the spark that he provided, his impact so great that he was heralded by the Spanish media as the one to break Villarreal hearts.
As it stands the Reds have earned around £100m from the Champions League thus far following last night's success, although with a Covid-related rebate due to UEFA from all participating clubs that figure will likely be closer to £97m. But should the Reds make it to the final and go on to win the competition then the prize money for making it to Paris and subsequently lifting the trophy would stand at around £43.2m, according to figures presented by football finance expert Swiss Ramble on Twitter.
That figure, added to the £84.8m already banked after the rebate takes the total up to £128m should the Reds win the competition, with that total potentially rising to around £130m when the additional game and TV money is factored in.
Last night's win was worth just over £13m to the Reds. Should they be successful in the final in Paris on May 28, whether that is against Manchester City or Real Madrid, then the turnaround that Diaz helped to orchestrate would land another £30m, making up that £43.2m figure. That would be more than what Liverpool's initial fee for signing Diaz was (£37.5m) and just £6m shy of the total sum that they are likely to have to stump up to Porto in time.
Those numbers don't include the better commercial partnerships that Liverpool can achieve through leveraging that success, nor does it include the potential increase in global merchandising that could arrive on the back of such a success. That is something Liverpool can do better than most others at given their 20 per cent cut of the sale of Nike/Liverpool merchandise globally.
Now, it wasn't just Diaz that hauled Liverpool over the line last night as a second half turnaround involved plenty stepping up to the mark. But such a unique lift provided by Diaz was undoubtedly the catalyst, and as FSG's hierarchy watched on from the US they would have been delighted to see yet another transfer win deliver a knockout blow, further vindicating the transfer strategy that they implemented but that has been taken to new heights by their knack of hiring the right people to guide it on each step of its journey.
Liverpool have made some mistakes in the FSG era when it comes to transfers, and few would herald Christian Benteke or Andy Carroll's time at the club a huge success. But in recent years the dedication to living and breathing analytics and ensuring that any players they sign have been scrutinised to such a level as to reduce the risk as much as possible, has meant that Liverpool have been able to continue to do what many others continue to attempt but struggle to achieve.
Getting that deal done in January from under the noses of Tottenham Hotspur has been both a competitive and financial masterstroke by all involved.
