It was surely with a knowing nod that Liverpool, still glowing from once again winning through to the Champions League semi-finals, discovered what happened to Manchester City the same night.
After all, they know all about what can happen when you take on a Diego Simeone side.
Their Champions League visit to Atletico Madrid in February 2020 brought about the beginning of the end of the Reds' reign as European champions, with some of the antics of the Spanish side leaving a bad taste in the mouth.
Certainly, rare are the occasions a manager has to substitute a player at half-time to avoid him being sent off due to provocation, as was the case with Sadio Mane in the Wanda Metropolitano.
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When Liverpool gained a modicum of revenge by beating Atletico home and away in this season's group stages, there remained an edge to proceedings with the Spaniards having a player sent off in both games.
So while the Reds on Wednesday safely negotiated a late Benfica flurry to set up a last four clash with Villarreal, City were embroiled in what seemed approaching an all-out war in digging out a goalless draw at Atletico to set up their own semi-final against Real Madrid and keep alive the prospect of an all-Premier League final between what are now indisputably the best two teams in Europe.
Before then, though, they clash swords for a second time in six days with their FA Cup semi-final at Wembley on Saturday.
And Simeone, so often the thorn in Liverpool's side, may have inadvertently done Jurgen Klopp a favour by imploring Atletico took City to the limit, both physically and mentally.
The Reds boss, though, is unconvinced. "I don’t know," he said on Thursday. "I didn’t see the full game, I saw a few highlights. We had it last week before we played City, we had an away game and arrived home in the middle of the next day, we stayed overnight (in Lisbon).
"Travelling is intense, definitely. Will it give us at advantage? I have no idea. We will see that. It was for both teams intense (in midweek) but I didn’t see the complete game from City yet and will do that this afternoon."
Indeed, while there were five days between the Champions League first legs and last Sunday's Etihad meeting between the Premier League's two title contenders, the sheer intensity of the 2-2 draw meant several Liverpool players were dangerously close to running on empty during the closing stages.
With less than 72 hours between the final whistle at the Wanda and the start at Wembley, there is notably less time for City to recover. And if Klopp to an extent gambled by making seven changes to his starting line-up against Benfica, the precarious nature of the tie meant Guardiola only made two alterations to his team.
Then there are the injuries. Klopp, of course, would sooner face a City at full strength, long having declared he prefers to be tested by the very best of the very best. But there's little doubt the potential absence of Kyle Walker and, in particular, Kevin De Bruyne will bolster Liverpool's chances of victory.
"We are in big trouble," Guardiola said in the immediate aftermath of Wednesday's game. "We cannot forget we played three days ago a tough game against Liverpool. We came here, we have a lot of injuries. I don't know what will happen in the next weeks."
Mind games? Most probably. Plus it's not as though Guardiola hasn't got extensive and expensive options to which he can turn.
But in a fixture where small margins are often so crucial, Liverpool have to capitalise on a possible advantage - and it could be thanks to Simeone.
