Juan Mata revealed there had been some banter between Spain's Manchester-based contingent in the build-up to Saturday's derby at Old Trafford.
The United midfielder is joined in the Spain squad by the likes of team-mate David De Gea and City rivals Nolito and David Silva.
Jokes have been exchanged among the quartet as Spain warmed up for the beginning of their World Cup qualifying campaign by beating Belgium in a friendly on Thursday.
Julen Lopetegui's men face Liechtenstein on Monday, but that is not all that has been on Mata's mind as Jose Mourinho and Pep Guardiola prepare to renew their rivalry.
"After the international break, there is a game coming next Saturday that I'm sure many of you are waiting for: the Manchester derby," the 28-year-old wrote on his blog.
"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 Premiership 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, although the truth is we are now focused on the games with the national team.
"After that, we will have plenty of time to think about this exciting derby."
Both sides have started with three wins from as many Premier League games, with City leading the way on goal difference.
United took the bragging rights last season, following up a 0-0 draw on home soil with a 1-0 win at the Etihad courtesy of Marcus Rashford's goal.