Hojlund was captured having a heated debate with Diallo after the full-time whistle had sounded as the former's double helped Manchester United to a 2-1 win over Czech side Viktoria Plzen in the Europa League.
The Dane could and perhaps should have had a third in second-half stoppage time.
With Plzen committing numbers forward in search of a late equaliser, United had several opportunities to put the result beyond doubt via counter-attacks.
One of those fast breaks forward included Diallo having the chance to square the ball from the right into the path of Hojlund, who had squeezed in front of his marker.
Had Diallo done so, Hojlund would have been in a strong position to score his third of the evening.
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Hojlund's frustration at Diallo for not playing the ball and giving him a chance to record a hat-trick was evident, as the two had words after the final whistle.
Some fans easily could have viewed the incident as a sign of disharmony among the players.
But Red Devils boss Amorim loved what he saw.
"For me, it's perfect," Amorim said in his post-match press conference.
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"We need to feel something. In this moment, we need to feel something.
"If we need to fight each other, it's like a family. For me, it's a very, very good sign.
"We need to feel something and that is important."
When asked if Hojlund and Diallo's squabble was a sign that his players care, Amorim believed the incident proved 'that is clear'.
"When you don't, you do nothing," Amorim said.
"When you care, you fight. With your brother, with your mother, with your father.
"For me, it's a very good sign."
Amorim also added he prefers his players to sort it out amongst themselves whenever they have a disagreement.
"I let the players and the captain to calm down the things," Amorim said.
"If I see that it is too much, I will go inside the dressing room.
"But it's their space, they have to talk, to fight. Again, for me, it's a very important thing."
The win over Viktoria Plzen also cemented Amorim as one of just three United managers to win their first two matches in a major European competition.
Only Sir Alex Ferguson and Sir Matt Busby had achieved the sensational feat prior.
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