When Julian Alvarez took the field against Boca Juniors in October he was already River Plate's brightest prospect, a young talent who was tipped for a strong future in the game.
By the time he walked off the Monumental pitch, though, he was on his way to stardom.
The 21-year-old netted twice in a scintillating Superclasico performance to give his side victory over their arch-rivals, and set in motion a stunning ascendancy which culminated in January's £14 million ($18m) move to Manchester City.
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Now, on Sunday, the now-River loanee lines up for what may well be his last Superclasico in front of the adoring Millonario crowd, and he will be desperate to go out with a bang in Argentina's biggest match of all.
Alvarez and River head into the clash as slight favourites over Boca, having made a strong start to the 2022 Copa de la Liga.
Marcelo Gallardo's men were able to put swiftly behind them a shock opening day upset to Union and have won four of their following five fixtures, with last year's league top scorer already sharing the lead this year with four strikes.
If anything, the club is even better placed this year, despite the looming – although the date is still to be confirmed – loss of their young superstar.
Buoyed by Gallardo's decision to extend his seven-year stay at the end of 2021 after lifting the Liga title, River repaid the coach's faith with a lucrative spending spree on fresh talent, bringing in talented playmaker Esequiel Barco from MLS, arranging a homecoming for the delightful Colombian Juan Fernando Quintero and bolstering the club's defence with the arrivals of Leandro Gonzalez Pirez and Emanuel Mammana.
It is Alvarez, however, to whom the entire River universe will turn in the derby for inspiration. In the fevered days that led up to the clash, no less a club legend than Ariel Ortega tipped the 'Spider' to repeat his October heroics.
“He is a complete player, there's a reason Manchester City and a coach like Pep Guardiola have bought him,” the ex-Argentina No.10 told TyC Sports.
“When you see him live his speed and power surprise you. He breaks through, drags the defenders away and when he shoots he does not miss. He is the best revelation we've seen in a while.”
Nevertheless, Sunday's clash, part of an entire round of derby matches across Argentina this weekend, will be no walkover.
Boca enter the Monumental with just one defeat under their belts and boast their own prolific striker and fan favourite in the shape of ex-Marseille man Dario Benedetto, who cut his stay in Europe short in January to return to Buenos Aires and has netted three times in four appearances so far.
The Xeneize have also appealed to supernatural forces in the build-up. Sunday will see the club jettison its famous blue and gold jersey for the first time ever in the Superclasico, in favour of a yellow change strip.
The reason for the switch? According to sports daily Ole, it is on the advice of a shaman who was hired to carry out a spiritual cleansing at the Bombonera, and who suggested they wear the new shirt to keep up the positive energy gained from last week's victory over Estudiantes.
“I love the shirt, it's very nice,” Boca boss Sebastian Battaglia stated when the inevitable press conference grilling over the jersey arrived on Thursday.
Gallardo too remained diplomatic, affirming, “each person believes what they believe and that's fine. I'm not one to judge anybody.”
Such appeals to superstition and ritual are an endearing facet of the Argentine game and one, along with the unrivalled passion and noise of local crowds, especially on big derby days, Alvarez will likely miss once his transfer to City is complete.
While it is still not certain whether he will move to the Etihad Stadium in June or after the World Cup in December, the forward's words leading into Sunday's Boca showdown suggested that he was gearing up for his final Superclasico.
“This week we'll be ready for what will be a great game,” he told reporters after last weekend's 4-0 drubbing of Gimnasia, during which the youngster netted one of three penalties awarded to River on the night.
“I am trying to enjoy every game, the day to day, training, I am enjoying every minute of it as much as I can. I might not have long left, it might have been different if I had left in December but I've got six months or a year and I have to make the most of it.”
Boca certainly will be hoping they have seen the last of their dynamic, ruthless young nemesis for the time being after Sunday's derby duel.
Meanwhile the Millonario cross their fingers in the hope that they may keep him for while yet, to spearhead their quest not only to retain the Argentine title but regain the Copa Libertadores title last won in 2018, at the expense of none other but their rivals on the other side of town.