The Brazilian star, Neymar faces a highly uncertain future at Paris Saint-Germain after fans chanted for him to 'f*** off' and leave the club outside his home.
He signed for the Ligue 1 giants from Barcelona for a world-record £198million fee in the summer of 2017.
Despite leaving nearly six years ago, Neymar appears to maintain a close relationship with some of his former teammates at the Catalan side.
So much so that Spanish outlet Sport report that the 31-year-old attended the Barcelona squad's celebrations as a 'surprise guest'.
The Spanish outfit, managed by club legend Xavi, secured the title for the first time since 2019 with a 4-2 win against local rivals Espanyol on Sunday night.
Neymar, who is said to be on holiday in the city, joined some of the players at the Carpe Diem nightclub following their success.
Sport says he has a good relationship with Barcelona stars including Sergio Busquets and Jordi Alba, with whom he won eight major trophies.
Neymar has also experienced success at PSG, winning the Ligue 1 title on four different occasions.
However, he is seemingly no longer a fan favourite in Paris despite currently rehabilitating from a long-term injury, and recently responded to the protests from fans outside his home.
"Don't let people put you in their storm, put them in your peace," he posted on his Instagram account.
Despite this, it is also claimed that he liked a tweet suggesting that he and co-star Lionel Messi were happier together at Barcelona.
The duo starred for the club from 2013 to 2017 and reunited when the latter joined PSG in the summer of 2021.
Like Neymar, Messi could also be on his way out of the club in the summer amid links with a move to Saudi Arabia.
A sensational return to Barcelona is also a possibility for the World Cup winner, who scored 672 goals during his previous stint at the Camp Nou.
Neymar's future on the other hand is not so clear, although Chelsea could reignite their interest in a move this summer.