Lionel Messi has called his start at former club Paris Saint-Germain "very tough", dubbing two successive failed Champions League bids a "massive disappointment".
"I came to Paris because I liked the club, because I had friends in the dressing room... it seemed easier for me to adapt rather than another destination I could have gone to," Messi told beIN Sports in an interview broadcast on Sunday.
"In reality, it was a very tough adaptation, much harder than I expected... with a new gameplan, new teammates, a new city.
"I arrived late, I didn't have a pre-season. The start was difficult for me, my family."
Messi, 36, signed for PSG in the summer of 2021 after 17 seasons at Barcelona, but will now head Stateside to Inter Miami in the MLS after quitting the French capital.
Messi's first season, during which he scored 11 goals in 34 games for PSG, was made harder after he contracted Covid during the winter break back in Argentina, meaning he was sidelined for a month.
"It took me time to refind my physical form," he admitted, adding that the 2022 World Cup in Qatar – which Messi won with Argentina – also took its toll.
"It's not an excuse but the World Cup played a big role. Some came back later than others, some were injured, like Neymar.
"I think, generally, the level of Ligue 1 and the Champions League was affected by the World Cup."
Messi admitted that Champions League losses to Real Madrid in 2022 and Bayern Munich this season were a "massive disappointment".
There were even sections of PSG fans who turned on Messi, whistling at him from the stands.
"In the beginning, it was great, I received a lot of encouragement... but later on a part of the Parisian fanbase treated me differently. The majority treated me well, but there was a rupture with a part of the public," he acknowledged.