Tottenham are on the hunt for defensive recruits before the transfer window comes to a close next month, with left-back an area being focused on.
Danny Rose is poised to leave north London permanently to join Serie A side Genoa, leaving Jose Mourinho with restricted options in defence.
Sergio Reguilon is a target, having caught the eye following an impressive season on loan with Sevilla, and Spurs are leading Manchester United in the hunt.
Mourinho has already bolstered his ranks this summer with the signings of Pierre-Emile Hojbjerg, Joe Hart and Matt Doherty but further deals are in the pipeline.
So, if Reguilon does move to Tottenham, what shirt number could he take? His current number 21 is occupied by Juan Foyth, who may move himself, but there are other options for the Spaniard.
No. 3
With Danny Rose poised to leave Tottenham permanently, the number three shirt is set to become available in north London and it stands out as the most likely option for Reguilon.
The number is usually associated with left-backs and has previously been worn by Gareth Bale, Young-Pyo Lee, Stephen Kelly and Mauricio Taricco since the turn of the millennia.
With Matt Doherty having already taken number two this summer, Tottenham could see another of their prime numbers taken by a new signing.
No. 13
Usually a number associated with the back-up goalkeeper, the number 13 has become available at Tottenham following Michel Vorm's exit.
Hiowever, new signing Joe Hart has taken the number 12 shirt and that has made the number available for Reguilon if he decided he'd like a double-digit number.
No. 14
Now vacant after previously being worn by Georges-Kevin Nkodou, the number 14 has previously been worn by the likes of Luka Modric and Gus Poyet.
That gives the number a nice bit of history, if Reguilon would like to follow in the pair's footsteps, but it's certainly not the most obvious choice.
No. 16
Another alternative option for Reguilon to take is the number 16, which has become available following Kyle Walker-Peters' permanent move to Southampton.
Previously worn by Kieran Trippier, Kyle Naughton and Kyle Walker, the number 16 has been associated with Spurs full-backs for a while and Reguilon could become the latest to follow suit.
