Cape Town - Manchester United midfielder Juan Mata has revealed that there is a rivalry developing in the Spanish national team ahead of the Manchester derby on Saturday.
Mata, along with Spain goalkeeper David de Gea, is expected to line up against Spanish teammates David Silva and Nolito when United take on City at Old Trafford this weekend.
Although they are preparing for a World Cup qualifier against Liechtenstein on Monday, Mata concedes the four players have already started to grill each other ahead of the big match.
Both Manchester clubs have a 100 per cent record after the first three Premier League fixtures of the season and it will also be the first clash in England's top flight between Jose Mourinho and Pep Guardiola, who had been involved in a fierce rivalry when managing Real Madrid and Barcelona respectively.
Mata said on his club's official website: "All of us are fully aware that this is a very special game, yet we have to understand that these are three points and don't get too crazy.
"Both teams have started the Premier League well and the expectations are high, as everybody can imagine.
"David de Gea and me have been joking with Nolito and Silva in the last few days."