The comments by the 29-year-old striker were made in the documentary ``Neymar & The Line Of Kings,'' produced by DAZN. An excerpt was published on the channel's Twitter feed on Sunday.
``Man, I think it will be my last World Cup,'' Neymar said. ``I am facing it like the last World Cup because I don't know whether I will be able to, mentally, to endure more soccer.
``I will do everything possible to get there very well,'' he added. ``I will do all I can to win it with my country and realize my dream, the biggest since my boyhood. I hope I can achieve it.''
Neymar will play with Brazil later on Sunday at Colombia in a World Cup qualifying match. The Selecao leads the 10-team round robin competition with 27 points after nine games.
The striker did not play in Thursday's 3-1 Brazil win at Venezuela due to suspension.
The match in Barranquilla will mark Neymar's return since the 2-0 win against Peru on Sept. 10, in which he turned in a key Brazil performance with an assist and a goal. Despite his efforts, Neymar made clear after the match that he is upset with the treatment he gets at home.
``I don't know what else I need to do with this shirt for people to respect Neymar,'' he said. Local media accused the striker of being out of shape in the 1-0 win at Chile earlier in September, which prompted the striker to walk around shirtless during training to show how fit he is.
Against Peru, Neymar overtook Romario as Brazil's top goal scorer in World Cup qualifiers, with 12 goals. He is also approaching Pele's record of 77 official goals for Brazil. The Paris Saint-Germain striker has scored 69 times for Brazil.
Neymar has so far played at two World Cups. In 2014, he picked up a back injury in the quarterfinals against Colombia, which stopped him from playing in the 7-1 humiliation against Germany in the semifinals.
In the most recent edition of the tournament, Neymar had just returned from a serious foot injury and turned in an unimpressive performance in Brazil's 2-1 quarterfinals defeat to Belgium. He left Russia amid heavy criticism for his apparently exaggerated reaction to being fouled.
Neymar won the 2013 Confederations Cup title with Brazil. He has also won the gold medal at the Rio de Janeiro Olympic Games. The striker was injured before the 2019 Copa America, which the Selecao won at home.
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