During his career Manchester United's legendary boss Sir Alex Ferguson came up against plenty of different adversaries, but not many had the same respect shown for them as now Chelsea boss Jose Mourinho.
The Portuguese manager first went head-to-head with Fergie as Porto manager, knocking out United in a Champions League giant killing.
Now of course Fergie is retired and Mourinho is back at Chelsea hoping to get one over on United in the Premier League title race.
And Ferguson has recently been waxing lyrical about his former adversary.
"It is unfair really. He’s good looking, he’s got that sort of George Clooney bit in his hair now. But I think he is a great example, he can speak five languages or whatever he can."
"He never played the game, by the way – you tell me how many presidents would give a manager a job who has never played the game? None. But he has done it.
"Then he goes and manages a small team in Portugal, then goes to Porto and wins the league, wins the Uefa Cup, wins the European Cup, goes to Chelsea and wins the league. Goes to Inter Milan.
"That is an example to anyone who wants to do well, you shouldn’t let the barriers get in your way if you want to get there."
Chelsea fans will certainly agree with the Manchester United legend, for once, on this one.