Lionel Messi remains the best player in the world in Ander Herrera's eyes and the midfielder expects Kylian Mbappé to dominate world football "for many years to come".

Messi ended a glorious 21-year association with Barcelona amid well-documented financial difficulties for the Catalan club as he moved to the Parc des Princes on a free transfer in August.

The Argentina international reunited with Neymar to form a formidable frontline with Kylian Mbappé, while Mauricio Pochettino also brought in Sergio Ramos, Achraf Hakimi, Gianluigi Donnarumma and Georginio Wijnaldum.

Paris Saint-Germain, buoyed by their new array of attacking talent, sit 13 points clear at the top of Ligue 1, although Messi is yet to fully fire as he continues to settle into life in France.

Messi netted 672 times in 778 appearances for his former club, but he has only found the net on six occasions for PSG across all competitions – averaging a goal every 219 minutes.

However, Herrera still believes Messi is comfortably the best player in the world and insisted Pochettino's side are learning to adapt around the forward, such is the 34-year-old's quality.

"Players of Messi's level shorten the acclimatization time," Herrera told Mundo Deportivo. "He will play the same way in France, in Spain, in Japan or in Madagascar.

"He has won his seventh Ballon d'Or and trains and enjoys as if he were only starting to play now. No training action is taken as a joke.

"At times we have already seen the best version of Leo, as against [Manchester] City at home, but I think it is also the responsibility of all those around him. We have to put ourselves at his service to get the best out of him. Normally, regular players have to adapt to a new context. 

"Now it is the other way around because we are talking about the best footballer in history."

Mbappé has outshone Messi thus far, the France international managing 15 goals – scoring every 134 minutes – and 12 assists across all competitions this term.

Indeed, since the 23-year-old scored on his PSG debut on September 8, 2017, against Metz, only three players – Robert Lewandowski (208), Messi (168) and Cristiano Ronaldo (157) – have managed more goals across Europe's top-five leagues in all competitions than Mbappe (147).

But Herrera believes Messi still holds the edge over Mbappé, who the Spain international thinks will dominate football for years to come.

"Kylian will be the best player in the world for many years to come, but we all agree that Leo is number one," Herrera added. "No doubt. Mbappe has an immense humility and desire to learn from Leo."

Former Clasico foes but now team-mates, Ramos also followed Messi as he ended a long-standing association with Madrid to move to Paris.

However, the center-back has been hampered by injuries and received a red card in just his third outing for his new side against Lorient on Wednesday, but Herrera expects his compatriot to become a key figure.

"Of course [It has not been easy for him]," he said of Ramos. "He's used to feeling important, playing and leading. But he has now been training for two or three weeks at a fantastic level and we are optimistic.

"It shows in his character and in the happiness he radiates."

With Ramos and Messi among a depth of talent on PSG's books, Herrera understands there is more pressure on PSG now to win the Champions League, though he feels Madrid are favorites for their Champions League last-16 tie in early 2022.

"We want to win the Champions League and we are going to try," he added. "There's no doubt. But just because we have Messi doesn't mean we're entitled to more than everyone else.

"We understand that people expect the best from us, but in Europe there are eight or ten other teams with the same chances of winning.

"A club that has 13 Champions League titles, against one that has not yet been European champions, has to be a slight favorite."