Messi has just completed his first season in Paris, finishing as a Ligue 1 winner.
He said, "What happened, happened and it was hard. It was a difficult change.
"There are no doubts about the Ballon d'Or, it's very clear that Benzema had a spectacular year and ended up winning the Champions League, being fundamental from the last 16 onwards in every game. I think there are no doubts this year."