Sir Alex Ferguson resumes his friendly rivalry with Jose Mourinho tomorrow night at the Bernabeu, but when the Portuguese manager visits Old Trafford in a fortnight's time, many will be wondering whether it will one day become a regular occurrence.
When Ferguson is forced to one day call it quits, there will be only the highest calibre candidates under consideration.
Jose Mourinho has won the Champions League twice - as many times as Sir Alex - and is a league champion in four different countries. He certainly fits the bill.
Yet not all agree with his potential hiring, namely Peter Schmeichel. United's 1999 treble-winning goalkeeper told Spanish newspaper El Mundo:
"He probably won't be his successor. I don't think the club would be happy with all the baggage Mourinho would bring with him.
"He would be a great candidate on a technical level, but I don't think the club would want all the external elements that would come with him.
"We've seen it at Chelsea, Inter and now with Real Madrid. He's a manager for three years – he doesn't last longer."
It is a fair point, Mourinho is yet to stay in a managerial job for more than three seasons anywhere. But what do United want? Do they want a manager capable of sustaining success in the short-term, or somebody with a 10-year plan?
The problem with the latter is, in the modern game, if you do not achieve instant success, then a manager will be fired, and the demand for United's next boss to be successful will be a pressure like no other.
Very few will be able to handle it, Mourinho probably can. If the club are prepared to take a chance on his 'baggage'.
What do you think of Schmeichel's comments? Is Mourinho going to be Ferguson's successor?
image: © tpower1978