Messi and Ronaldo have battled it out for the title of best player in the world for eight years.
One of the pair has won the Ballon d'Or for the last seven years, with Ronaldo finishing second in the voting ahead of Messi when Kaka won the award back in 2007.
But Neymar has impressed this season alongside Messi, scoring 26 goals in all competitions for the Catalan club after netting just 15 in his first season at Camp Nou.
Ferguson said: "The boy Neymar gets a lot of publicity about the potential he's got, but I think that's still to be seen, still to be fulfilled. Certainly, most people I speak to speak highly of the boy.
"When I had Anderson at United, he spoke volumes about the boy's ability. So hopefully he'll be the next one who'll produce the type of talent we see in Messi and Ronaldo.
"You'll always look at clubs like Bayern Munich, Barcelona, Real Madrid and Manchester United to produce that kind of player you're talking about, but to be honest, I'm not sure there's one sticking out at the moment."
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