Carles Alena has given up his No 21 shirt so Frenke de Jong can honour his late grandfather.
De Jong's social media accounts have the No 21 is his usernames already.
But De Jong was not given a shirt number on his arrival and according to Mundo Deportivo asked Alena for the No 21 shirt.
Alena generously gave him the number and will decide on a new number in the coming days.
De Jong revealed his grandfather died on his 21st birthday and he pays tribute to him through the number.
'I feel comfortable with that number,' De Jong told Dutch magazine Voetbal International.
'I could easily play with another number, you know, it's not a problem, but it is nice that it also gives people a way of recognising me.
'I brought my whole family to my presentation in Barcelona, except my grandfather Hans de Jong, my father's father.
'He died on the day of my 21st birthday. Unconsciously it is also a kind of tribute. He was a huge football fan.'
YourHighness
49
Carles Alena knows the importance of family, and gives up his number so De Jong could use it and honour his grandfather. Respect Alena!