Liverpool's ball boys became the centre of attention during their famous 4-0 win over Barcelona at Anfield.
They were instructed by the club to act quickly on the touchline to take advantage of Barca's defence, which was often not set and ready to go in time.
For Divock Origi's second and Liverpool's fourth goal, the ball-boy's quick thinking allowed Trent Alexander-Arnold to construct a genius corner routine for Origi to slot the ball home and win the tie.
In a game of such fine margins, the smallest details are crucial.
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And it's something that Jose Mourinho is a huge, huge fan of and he has now praised Liverpool to the rafters for implementing their ball-boy strategy.
Mourinho told RT: "You want a quick throw-in, the ball boy needs to know that you want a quick throw-in. The ball needs to arrive fast.
"The goalkicks, the tempo of the game, the ball boys can also play a part in a good structure.
He added: "In this game, the kid, very intelligent, very bright."
Mourinho then appeared to take a swipe at his former club Manchester United, where he tried to make significant alterations to their ball-boy strategy by using academy players instead.
"I had a club where they never understood how important the ball boys are," Mourinho stated.
"I was a ball boy, a top ball boy… when I was a ball boy, I even knew where the players wanted the ball for a corner, so they didn't need to touch the ball.
"(At) a real football club, every detail is very, very important."
Never change, Jose.
Mourinho's stint in punditry has been a massive success, with many demanding the English channels to bring him into the studios.
However, they may have missed their chance, with the Portuguese likely to return to management sooner rather than later.News Now - Sport News