Liverpool boss Jurgen Klopp was forced to play 18-year-old goalkeeper Shamal George as an outfield player in the second half of the Reds' 2-0 friendly win over Huddersfield.
With all of Liverpool's outfield substitutes already on the pitch, Klopp was faced with a dilemma on the hour-mark when Lucas went down with a hamstring injury.
The Brazilian could not continue, and Klopp turned to his reserve 'keeper to play off lone striker Danny Ings, much to the crowd's delight at the John Smith's Stadium.
Asked about whose idea it was to bring on George, Klopp said: "They told me from the bench after I'd organised the system with 10 [men] and they said, 'Come on, we have Shamal'."
The crowd lapped up the bizarre situation, and George nearly capped off his display with a goal after lobbing the opposition 'keeper, only to be flagged for offside.
Minutes before the end, Liverpool won a penalty after Ryan Kent was tripped in the box, with supporters calling for George to take the spot kick.
However, boos followed as Alberto Moreno instead slotted home, with Klopp insisting that some respect had to be shown to their opposition.
"It is nice when the crowd calls it in but at 1-0 in no game in the world should you make a 'funny' decision," he said.
"If it is 4-0 or 5-0 you can think about it but even then it is a lack of respect for the opponent."
It was a comfortable night for Liverpool in the end, with Moreno's penalty coming after a Marko Grujic strike.
"The game was difficult. The first half we should have scored more," added Klopp.
"We had a few big chances and played some wonderful combinations so it was really good. But I was not too happy with the concentration level in the first 20 minutes.
"I said to the boys it was not bad but if we trust a little bit too much in our skills than a team performance it is not the best decision to make."
Liverpool will now prepare for a trip to the USA, where they face Chelsea in the International Champions Cup next Thursday.
However, despite Philippe Coutinho missing a first-half penalty, Liverpool's win was sealed late one when Martin Cranie tripped Ryan Kent in the box, with Moreno keeping his cool from the spot.
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