Rio Ferdinand revealed whether Ronaldo Nazario or Sergio Aguero was the more difficult striker to come up against. READ MORE: Who is Sergio Aguero? Step inside the life of the Premier League icon with 260 Man City goalsIn January, Ferdinand revealed that Aguero was one of his most challenging opponents during his playing days, noting that he felt that he had to be on his A-game when facing a player of his calibre. However, Ronaldo Nazario famously scored a stunning hat-trick against Rio Ferdinand’s Manchester United side in the Champions League in 2003. Rio Ferdinand reveals the harder striker…