The first time Leny Yoro had his name chanted by Manchester United supporters was as he prepared to take his most important kick of a football.

Yoro's name was hollered repeatedly to the familiar tune of Papa's Got a Brand New Pigbag, a song released 23 years before Yoro's birth. United fans have recently serenaded Casemiro to the same ditty but that Sunday at the Emirates Stadium possibly signalled a changing of the guard.

United first team coach Emanuel Ferro listed Yoro as the third penalty taker in the FA Cup third round against Arsenal. That meant he was next up after Kai Havertz lost his nerve. Yoro was nerveless.

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Yoro was involved in a penalty shootout with Lille against Aston Villa last season but was not one of their five takers. Elevating a 19-year-old on his ninth United appearance to third in the spot-kick pecking order at the Emirates Stadium's Clock End was dicey.

Of United's five to step up, Yoro was the most unexpected. He never wavered and David Raya could not have dived further away from the ball.

That conversion elicited a louder roar than when Bruno Fernandes and Amad put the ball past Raya with the first and second spot-kicks. After Yoro returned to the centre circle and high-fived his team-mates, Fernandes prodded fifth-in-line Joshua Zirkzee in the chest. Zirkzee immediately steeled himself for the potential match-winning kick. Yoro was the first to leap onto Zirkzee when he triumphantly waved to the United fans.

It capped a week to remember for Yoro. The teenager's last-ditch tackle on Darwin Nunez at the Kop end will be replayed and he did not flinch amid the high stakes at Arsenal.

Then Yoro was the preserve spread over Southampton winger Kamaldeen Sulemana's toast. Yoro's worst night in a United shirt came four days after his best.

It is a rite of passage for a newly-signed United centre back to have a chastening start. Gary Pallister had the 5-1 at Maine Road, Nicolas Anelka gave Jaap Stam the run-around in the Charity Shield, Rio Ferdinand had false-starts through injury, Nemanja Vidic was part of a defence that shipped four goals at Blackburn on his maiden start, Victor Lindelof pulled two hoods over him as he left Huddersfield, looking like a criminal leaving court. He was guilty of letting Huddersfield score twice. Lisandro Martinez had Brentford.

The Emirates was the scene of Yoro's belated debut last month. He has worn that navy kit three times against Arsenal now and the first delayed the start to his United career. A freakish tangle with Gabriel Jesus in pre-season left him with a fractured metatarsal.

Yoro conducted the majority of his rehab with the first team physiotherapist Ibrahim Kerem. The Australian oversees United players' recovery from injury and Yoro used his rehab to increase his physical preparations to play in the Premier League.

People at Carrington found that Yoro's demeanour never changed during his four months away from the pitch. United treated the injury as a positive (something Sir Alex Ferguson swore by), framing it as an opportunity for Yoro to settle in Manchester and become accustomed to his new surroundings after arriving from France.

Although Yoro sustained the fracture in a pre-season friendly in Los Angeles, he remained with the team in the States with the aid of crutches, and had surgery back in the UK. United favoured their own facilities after Rasmus Hojlund's scan for a hamstring injury in America proved inconclusive.

Yoro is continuing to work with an external masseur who he does additional recovery with him at home either in the evenings or on days off. He resumed team training in early November but did not play for another month. Yoro had been pencilled in to start for the Under 21s against Altrincham in the week Amorim took over training but he was withdrawn from the squad.

That fuelled expectation that he would be involved in Amorim's first match in charge at Ipswich Town. Yoro did not travel and had to wait another ten days until he received a train ticket for Euston for the Arsenal game.

"I think he's a special talent," Ruben Amorim said on the eve of Yoro's first appearance. "You have to be careful in this first moment, because we didn't have too many trainings together, he is training not alone, but with a small group of players.

"He is really fast, he is a modern defender and that is good when you want to press high and you leave a lot of strikers, especially in this league one against one, I think he can manage that. He is very good with the ball, so I'm really excited. I have to be careful. We have to manage the load and the minutes in the beginning but I am really excited to see Leny Yoro play."

United staff say Yoro is extremely laid back and mature. Some of the club's academy players regarded as high potential are older than Yoro, who turned 19 on November 13.

He has struck up a quick bond with Kobbie Mainoo. The pair are the same age and did rehab at the same time after Mainoo sustained a hamstring injury in early October. Andre Onana has become a mentor, as a fellow French speaker.

Yoro's idol is his compatriot Raphael Varane. Varane was a teenager playing in northern France at Lens in 2011 when he had to choose between Real Madrid and United. Varane was swayed by Madrid ambassador Zinedine Zidane's in-person intervention. Thirteen years later, Yoro made the opposite choice.

Varane, released by United in the summer, spoke with Yoro as he mulled over United or Madrid. There was contact with a handful of former United players and all were requested to remain mum about their involvement. Ferdinand, with approval from the club, broke ranks and his influence was publicised widely and wildly. Club staff say Ferdinand was genuinely helpful in persuading Yoro to choose Manchester over Madrid. Yoro inherited Vidic's old number 15.

Some figures at United feel Varane's departure has deprived the defence of experience and leadership. Lisandro Martinez is said to have been somewhat bereft without his favoured defensive partner whom he lined up with in two cup final triumphs.

Before Varane signed for United, he requested clips of their defending at set pieces from the previous season to prepare as diligently as possible. Yoro is big on personal analysis and brushes up on his homework ahead of facing opposition forwards..

His parents and siblings have not moved to England, so he has bought a dog called Dougie - not Duggee, the CBeebies favourite - to keep him company. His three younger brothers, Romeo, Eden (not named after the former Lille winger Hazard) and Estenban, are also talented footballers and have stayed in France to pursue their own futures in the game.