The 16-year-old winger has emerged as one of the most exciting prospects in United’s academy, but his future at Old Trafford is increasingly uncertain after a breakdown in relations between the club and his representatives.
According to Sky Sports, Real Madrid are positioning themselves to sign Gabriel in the January transfer window, although there has been no contact between the clubs at this stage. The teenager remains registered with United until the end of the season.
Gabriel, who turned 16 on October 6, has not returned to training at United since submitting a de-registration letter in September. He has instead been working with private coaches in Spain.
His family are understood to be frustrated with the pathway available to him at Old Trafford, particularly over opportunities to progress towards the first team. They believe his development could be better served by a move to one of Europe's leading clubs.
United, however, have taken a more cautious approach, prioritising his physical welfare and long-term development rather than rushing him into senior football.
A key development is Gabriel's Cypriot passport, obtained through his mother's Greek-Cypriot heritage. The document could allow him to move to a club within the European Union before turning 18, despite the restrictions generally affecting British players following Brexit.
The teenager had attracted interest from several major European clubs, including Barcelona and Paris Saint-Germain, but Real Madrid are now considered favourites to secure his signature.
Gabriel has already demonstrated his potential at youth level. He scored a hat-trick on his UEFA Youth League debut and had been expected to challenge for a place in United's senior squad after impressing during the club's pre-season tour.
He was also tipped to become Manchester United's youngest debutant in September's 3-2 Carabao Cup defeat against Brighton, although that opportunity did not materialise.
United would be entitled to compensation if he leaves, although the amount is expected to be lower if he joins an overseas club. The club have also reportedly considered legal action should a transfer take place in circumstances they believe breach the relevant rules.
For now, Gabriel remains a United player, but the reported agreement with Real Madrid represents a significant step towards an increasingly likely departure.