Any customer with a specific printing request at the Old Trafford Megastore will be warned that squad numbers are subject to change and refunds will not be offered.

Demand for Kobbie Mainoo's shirt is certain to soar but he is the number 37 and worthy of an upgrade. Erik ten Hag considered handing the number seven to Alejandro Garnacho last summer and the United app even teased the possibility. It went to Mason Mount.

Three, four and nine are the prominent squad numbers vacant at United. Matthijs de Ligt is the number four at Bayern Munich and Joshua Zirkzee has the '9' on the back of his Bologna shirt.

The '2' is likely to become available given United's eagerness to sell Victor Lindelof after seven years. Thirteen, 15 and 19 are also available.

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After United's double double triumph in 1995-96, the five "kids" Alan Hansen opined United would win nothing with had their squad numbers bumped up. Gary Neville went from 20 to two, David Beckham 24 to 10, Nicky Butt 19 to eight, Paul Scholes 22 to 18 and Phil Neville 23 to 12.

Garnacho was upgraded last year and Mainoo, the academy's latest poster boy, merits a number more befitting his indispensable status. He is England's number 26 at the European Championship and that is available at United.

The quirk last season is Garnacho started it with '49' stitched to his kit in United's first three games. United's squad numbers were not confirmed until after the transfer window had closed - three games into the season.

United waited for Mason Greenwood to leave on loan to redistribute the '11' to Rasmus Hojlund, who was the number 17 at Atalanta. Garnacho took the 17, vacated by Fred before the start of the season.

Cristiano Ronaldo sported '17' at Euro 2004 and the 2006 World Cup for Portugal during Luis Figo's last hurrahs on the international stage. Garnacho did not get the seven but his name still rests above the number.

Mount is the latest to fall under the number seven hex. Michael Owen, Antonio Valencia, Angel di Maria, Memphis Depay, Alexis Sanchez and Edinson Cavani all fared better in their first year at United. Valencia requested to revert to his old number 25 after a year in an attempt to improve his fortunes.

Managers can be fastidious over a player's number. Louis van Gaal altered James Wilson's number from 47 to 49 as he superstitiously felt a striker should have a '9' in their squad number. Eric Bailly had the number three revoked while he was still at United last year and it has not been reassigned.

Jose Mourinho passive-aggressively downgraded Marcos Rojo from number five to number 16 in 2018 amid his desperation for a centre half. The '5' was eventually taken the following year by Harry Maguire, with Mourinho long since sacked.

The 19-year-old Mainoo would be in eclectic company if he became United's latest midfield 19. Butt cemented his place in the United midfield as the 19 in 1995-96 but fellow midfielder Eric Djemba-Djemba donned it between 2003-05.

It is unlikely that was a regular request at the Megastore.