The Argentina great believes it's difficult for the pair to replicate their club form on the international stage but says they are both capable of starring in Brazil.
The Real Madrid and Barcelona stars have lifted the Ballon d'Or six times between them and dominated the game's greatest individual prize since Ronaldo was named the world's best player for the first time in 2008.
However, despite their incredible exploits at club level, critics have questioned their influence for Portugal and Argentina, but Maradona has backed both to shine at the World Cup in Brazil.
The Argentina great told the Times of India: "If an individual inspires the team with his brilliance, it helps immensely. That is why I believe the presence of Messi and Ronaldo will help Argentina and Portugal play better.
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"These two are the best of this generation and both are yet to play at the best of their abilities in the biggest tournament. It is difficult for them to recreate the magic that they produce while playing for their clubs, but they have the ability to do so. A manager has to ensure an environment where the team's goals are never sacrificed. At the same time, he must ensure that the gifted individual gets the space to express himself."
Maradona - who famously inspired Argentina to World Cup glory back in 1986 - then spoke of the challenge posed by Louis van Gaal's Netherlands.
The Oranje were runners-up at the 2010 tournament after losing out to Spain 1-0 in the final, but are not expected to be among the front-runners this time around.
The 53-year-old was left dismayed by their physical approach four years ago, but spoke highly of the star names at Van Gaal's disposal.
"The Netherlands have always produced exciting footballers. Arjen Robben is definitely one of them. Under Louis van Gaal, Robin van Persie has played well.
"But I was not happy with the football the Dutch played in the 2010 final. I expected skill to dominate, while they were intent on exerting physical power."