The Brazilian has 'liked' a couple of tweets on Twitter that criticized the French wonderboy
Tensions between Paris Saint Germain superstars Neymar and Kylian Mbappe are boiling after a row over who takes penalties emerged at the weekend.
Post-match, Neymar also 'liked' social posts on the matter that were critical of his French teammate.
The two players were both signed in the same summer of 2017, and have enjoyed a pretty incident-free relationship up until now.
When Mbappe recently snubbed Real Madrid and decided to sign a three-year contract extension at the Parc des Princes, however, it was reported that the 23-year-old was handed carte blanche and would effectively act as an informal sporting director able to make suggestions on who should be appointed and dismissed.
With ex-sporting director Leonardo and first team coach Mauricio Pochettino already shown the exit door, it was said that Mbappe also requested that Neymar be sold.
This hasn't come to fruition yet with the current transfer window closing on September 1, but the two appear to be on a collision course due to events that occurred during and after PSG's 5-2 home win over Montpellier where both players scored.
At one point in the tie, Mbappe stepped up to take a spot kick while appearing to have succeeded Neymar as PSG's penalty taker.
Missing with his attempt, he then insisted on snatching away a second from Neymar who refused to entertain his request and converted on his way to an eventual brace.
Ever present on social media, Neymar was caught liking a Twitter post that took a dig at his teammate.
"It's now official, Mbappe is the penalty taker at PSG," read the Portuguese tweet posted by Neymargiabr.
"Clearly this is a contract thing, because at no club in the world that has Neymar would he be the second taker, none.
"It seems that because of the contract [extension], Mbappe owns PSG!!!"
Elsewhere, Neymar also 'liked' another similar post that explained how he "scored and humiliated" Montpellier's goalkeeper by taking a penalty.
"Mbappe took a really bad penalty and missed. After the game, the coach said Mbappe will be the main penalty taker this season. It's absurd!" the tweet went on.
Mbappe was also singled out for general criticism after a clip showed him walking away and giving up chase for the ball when it was clear that a pass wouldn't come his way.
By detractors, he was called a "hype" job and a "monster", whose attitude "sucks".
According to RMC Sport, though, who allegedly spoke to club sources, Mbappe's evening had been blighted by "personal problems" that the 2018 World Cup winner still wanted to play through.
PSG's new coach Christophe Galtier also tried to play down Mbappe's sulking noting that with Mbappe playing his last game three weeks ago, he knew that the match was "going to be tough on a physical level for him".
"He's a competitor. He wants to be good and he wants to be good quickly, but a top footballer is not on and off like that; it takes a little time to regain 100 per cent of his athletic abilities.
"When he's at 100 per cent, he'll make the difference even more. These are players who like to score, who want to score, who attack. It's a bit normal for him to be disappointed at being a little short physically compared to his teammates," Galtier concluded.
Up next for PSG is an away trip to 2020/2021 Ligue 1 champions Lille, and it will be interesting to see how things pan out between Neymar and Mbappe with Lionel Messi perhaps a peacemaker if things escalate further.