Whenever a 18-year-old creates club history in a crucial European match against City, it naturally attracts praise and attention.
During his maiden start in the tournament - and fifth game for the team - Thiago Pitarch made a strong impression as the 15-time European champions secured a 3-0 last-16 first leg advantage at the Bernabeu.
The teenager, who also made his club debut in the play-off round a few weeks prior with a cameo off the bench at Sporting Lisbon, then helped Los Blancos overcome the English Premier League side in the midweek second leg to confirm a last eight place.
Aged 18 years old, the midfielder became the club's youngest player to begin two matches in the Champions League's latter rounds, beating star Vini Jr's record by a week and a half.
This talent is the latest to emerge from the famed youth system and is quickly establishing himself as one of Alvaro Arbeloa's most promising protegees.
He joined Madrid from CD Leganes in 2023, having previously been with Atletico and Getafe academies, and initially featuring for the Juvenil C team, where he rapidly created a strong impression.
He worked his way up to the B team and it was in a pre-season game in which they played against the academy's first team, then coached by the former defender, where the youngster is said to have drawn the eye of the present manager, who took over from the previous coach in January.
Spanish media would later label the moment as "an instant connection," adding Pitarch stood out not only for his skill on the ball, but for the vitality, personality and drive he added to the side.
In the pre-season of 2025, ex-manager Xabi Alonso called up Pitarch to practice with the first team and gave him minutes in the warm-up matches.
Yet, it was Arbeloa's appointment that became the defining moment in his development as he came on as a second-half replacement in each leg against the Portuguese side that led to the clash with Manchester City.
"I've dreamed of this each night before going to bed, the first day I started playing football, each day you go to train and every day you play a match," said the player following his debut.
"I've just achieved my ambition with the greatest club in the planet and in the best competition."
Handed a starting debut in the Spanish league against his former club - where he was for four years after moving from Atletico in 2018 - he has kept his place for the next four as injuries to Bellingham and Dani Ceballos provided an opportunity.
Pitarch has seized it with displays that have defied his age and inexperience.
"He's a very quick player, and you can see his capabilities," remarked Arbeloa. "He's incredibly energetic, with great stamina, work-rate and movement."
The player's mindset has also stood out to his coach.
"His greatest quality is his personality," added Arbeloa. "He constantly demands the ball, and when pressed, he remains unfazed.
"I understand fans might be astonished to see him make his debut in a European fixture, but he's playing because I had total trust in him to perform his normal game.
"Thiago will continue to get opportunities with the main squad. It's a pleasure to coach a player like him."
Born in a Madrid suburb, in the Madrid region, and grew up deeply involved in the local game, progressing through local academies before entering the club's famous La Fabrica system.
He possesses dual Spanish and Moroccan nationality, giving him the choice to play for either country at the highest level.
Under international regulations, footballers may represent multiple nations at junior level without being permanently tied, with the final decision only binding once they play in a competitive senior international match.
He has featured for the Spanish national team at youth level, representing both the under-19 and under-20 teams, and took part in the 2025 Fifa Under-20 World Cup, where Spain made it to the last eight.
Nevertheless, he has not yet decided to any senior national team, who are watching his progress with interest.
Speaking recently, Pitarch confirmed: "I haven't made my ultimate choice so far. My situation is positive with Spain, but I will reach a conclusion soon."
His situation mirrors that of other bi-national players such as club colleague Brahim Diaz and Barcelona forward Lamine Yamal. Whereas teenage Yamal opted for Spain, Brahim opted to play for Morocco.
At present, Pitarch's focus is on making his mark in the Madrid lineup and rewarding his manager's belief.
He played 74 minutes in the two-one win at City, which completed a five-one aggregate success and a last-eight tie with the German champions.
He was replaced by fellow youth graduate in Angel underscored Arbeloa's trust in younger players to aid the team pursue future success.
Following his notable contributions so far on the Champions League, Pitarch is expected to play a key role in that.
"The manager treats me the identical way. We deal with it very normally. I try not to overanalyze it too much - I have to earn my minutes on the field," he commented after the success at Etihad Stadium.
Elara Vance is a tech journalist with over a decade of experience covering emerging technologies and consumer electronics.