Manchester United manager Jose Mourinho bristled when asked if he would shake Pep Guardiola's hand, insisting he has a "normal" relationship with the new Manchester City boss.
Foes during their time battling for LaLiga glory with Real Madrid and Barcelona, the pair now share the same city and will be vying for Premier League success.
Their resumption of battle comes in the unlikely setting of the Bird's Nest stadium in Beijing, where both managers faced questions related to their sometimes fractious battle in Spain.
Guardiola was bemused when asked if he would shake hands with Mourinho, whose bemusement was even clearer when a similar question was put to him.
"To qualify the question I would use some unpolite words," he said. "Of course, I shake his hand. Why shouldn't we?
"I don't understand the question to him and I don't understand the question to myself.
"We work together in Barcelona for three years, we were opponents in other clubs but we are just professionals and we have a normal relations.
"Why shouldn't we shake hands? I don't see the reason for the question."