Barcelona have been unable to retire Lionel Messi's No 10 shirt due to rules enforced by LaLiga.
The Catalans waved goodbye to the greatest player in their history after his contract expired.
Financial complications meant they were unable to retain his services and the Argentine gave an emotional farewell on Sunday.
Messi has worn No 10 for over a decade having inherited it from Ronaldinho in 2008.
There have been calls for Barcelona to retire the number in tribute to the six-time Ballon d'Or winner.
However LaLiga rules state that each season a club must name their 25 first team squad players for registration, and they are assigned shirt numbers 1 to 25 inclusive.
If they were to retire the No 10 shirt they would only be able to register 24 squad members, thus giving themselves a disadvantage.
It means Messi's old shirt number will have to be handed down despite plans to leave it vacant.
The 34-year-old is close to securing a move to PSG on a two-year deal with the option of a third.
A switch to Paris will see him reunite with former team-mate Neymar, whom he played alongside at the Nou Camp for four seasons.
The duo could help form a historic front three that also features Kylian Mbappe, provided the Frenchman extends his contract at the Parc des Princes.
Messi conceded at the weekend that he wanted to stay at Barcelona and was heartbroken that his long association with the club was ending.
He said: "We had everything agreed but, at the last minute, it couldn’t happen [Messi staying at Barcelona]. I’ve heard lots of things being said about me, this year I wanted to stay and I couldn’t. Last year I didn’t want to stay, and I said it.
"This year I wanted to stay. I did everything possible but the club couldn’t do it because of La Liga.
“We have to take it and move forward.”
He added: "No doubt, this is the hardest moment. We got hurtful defeats but football give you a chance to revenge that. But there is no turning point to this”
“I feel very sad now as I have to leave a club that I love. I did not expect this. I always told the truth. Last year I wanted to leave, this year I did not want to leave”
Messi's imminent move to PSG means he could end up taking on Barcelona, but the forward insists he remains committed to winning trophies with another Champions League on his wish list.
"People know me, they know I am competitive, I want to keep winning," he said.
