The Ivorian winger was a bit-part figure under Erik ten Hag but has now risen to become the main man for Ruben Amorim.
Amad bagged his first Red Devils hat-trick in a 3-1 win over Southampton to become the club's second-youngest Premier League treble scorer behind Wayne Rooney.
His heroics were also the club's first league hat-trick since Cristiano Ronaldo claimed the match ball against Norwich in April 2022.
At the time of Ten Hag's axing on October 28, the 22-year-old had started just 12 games for United since his arrival in 2021.
His contract was due to expire at the end of the season and he'd been loaned out to Rangers and Sunderland for the 18 months prior.
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However, by January 16, Amad has matched his 12 games started since Ten Hag left under Ruud van Nistelrooy, and now Amorim.
The Ivory Coast international has penned a new long-term deal and scored against Liverpool, Manchester City, and his Saints hat-trick.
His influence is also being felt off the pitch, with Amad debuting several new celebrations to coincide with his scoring run.
What was Amad's old celebration?
The Man United starlet had previously been known to cover his right ear and left eye whenever he found the back of the net.
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Amad had revealed the gesture was a tribute to his late friend and former Atalanta teammate, Willy Braciano Ta Bi - who sadly passed away in February 2021 due to liver cancer.
Speaking after scoring his first United goal against AC Milan at Old Trafford in the first leg of the Europa League last-16 tie in 2021, Amad told the club website: "My first thought was… mamma mia.
"I have scored a goal in a United shirt! I couldn't believe it. My second thought was for Willy.
"Willy Braciano Ta Bi, my former team-mate, had died a couple of weeks earlier.
"Willy was a good friend of mine, another Ivorian in the youth team at Atalanta, and he had always showed me a specific goal celebration and he said that when he scored his first goal for the Atalanta first-team, that was how he was going to celebrate.
"So, as soon as I scored against Milan, that came into my mind. Celebrate like Willy.
"So I did his celebration. I wanted to remember him like that.
"I had to remember my good friend. It was a very emotional moment for me, as well as being a great moment in my career."
Amad continued honouring his friend in the following seasons since, but has added several other unique celebrations to his arsenal.
In addition to a standard kissing-the-club badge gesture, the forward has also been motivated to emulate a future Real Madrid superstar.
During Van Nistelrooy's interim spell in charge, Amad celebrated a goal by putting his right hand on his heart while holding up the index finger of his left hand.
He explained: "Yeah, this celebration. I saw this first with Arda Guler, who plays for Real Madrid. I tried to do the same celebration because I like [it]."
"This was the game against PAOK in the Europa League where I scored two goals, we won in Europe after one year [of not getting a victory], so it meant a lot for me and the team."
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"Yeah, I like him [Guler]," Amad smiled. "He's a good guy, a good young player. A top player who plays for Real Madrid, one of the best right now in the world.
"So, I saw his celebration, so I tried to copy him because I like his celebration. Maybe the next goal, I don't do the same or maybe I do my celebration. But, right now, I'm doing this!"