The Real star was named the world footballer of the year in 2016 to go within one of Messi's record tally of five, following a season in which he won both the European Championhsip with Portugal and the Champions League crown with Los Blancos.
The former Manchester United star is the favourite to win the award again this year after he also led Real to the La Liga title and the Champions League crown during the 2016-2017 campaign, scoring 12 goals in 13 games, including a brace in the final in the 4-1 win over Juventus.
Messi meanwhile netted 54 goals in 52 appearances at Barcelona but was only able to help the Catalans to clinch the Copa del Rey during Luis Enrique's final season in charge.
Valverde, however, has played down the importance of the individual title after pointing out that Messi is the best player in the world even if Ronaldo matches his tally of five Ballon d'Or titles.
"We all know who is the best player in the world. This subject about giving the Ballon d'Or to one player or another doesn't worry me," Valverde said in the press conference ahead of the Champions League visit of Olympiakos on Wednesday night (18 October.
Pressed whether he would be surprised if the Real star beat Messi for the award again this time, Valverde insisted: "I have already responded to that. I am not focused on other players. You don't need a Ballon d'Or more, less, a gold, a silver or a bronze to know that Messi's the best in the world."
Valverde's strong support to his Barcelona star comes only a day after Zidane refused to be drawn on the Ballon d'Or debate when asked whether Isco would deserve to be on the podium alongside Ronaldo and Messi.
"I'm not going to talk about the order of the ballon d'or candidates. It's a prize that a jury votes on," Zidane said in the press conference ahead of Real Madrid's clash with Tottenham. "I like Isco a lot because he's always creative and tries things. Players who try thing to always end up being successful."