It really is a joy to watch Neymar and Kylian Mbappe share a football pitch.

The Paris Saint-Germain duo have been banging in goals for the Ligue 1 leaders this season, and they were at it again during a 2-1 win over Lille on Friday evening.

Mbappe opened the scoring in the 70th-minute before Neymar doubled the hosts’ advantage six minutes before the final whistle.

Lille snatched an injury-time consolation goal from the penalty spot via Nicolas Pepe, though it mattered little as PSG became the first team to win their opening 12 matches of a season across Europe's big five leagues.

Incredibly, Thomas Tuchel’s are already 11 points clear at the top of Ligue 1 with a colossal goal difference of 34 - 23 better than their closest rivals Lille.

As the two leading goalscorers in the French top-flight, Mbappe and Neymar have been key figures in what’s shaping up to be a mere stroll to a sixth title since 2013.

In league action alone, the former Monaco striker has contributed to 15 goals this term, scoring 11 and assisting 4.

Similarly, the Brazilian has registered nine goals and four assists - meaning the pair have had a hand in almost 70 per cent of PSG’s goals to date.

When you look at what Mbappe and Neymar are achieving together in Paris, they’re difficult to separate as candidates for the title of the best player in the world.

Lionel Messi is arguably the most widely accepted holder of that particular title at present, but according to Xavi, Mbappe still has much developing to do before he can enter the conversation.

“He's a very superior player physically,” he told Catalunya Radio, via FourFourTwo.

“It's impressive that at his age he has those differences, but he could also get stuck, it's very difficult to predict.

“He still has no football maturity but, he could be one of the good ones. He is so strong, but that does not always work in elite football, he has to learn to think.

It seems slightly harsh - but Xavi does make a fair point.

The Al Sadd veteran also claims Neymar - whom he played with at Barcelona for two years - needs to work on the mental side of his game.

“Neymar is the player that I have seen, if he manages to acquire that maturity, that might be more like Messi.”

It’s an intriguing insight into two of the most brilliant talents in world football.

And coming from a man who’s worked with the absolute best, Neymar and Mbappe should certainly consider Xavi’s assessment.