They formed one of the biggest managerial rivalries that the Premier League has ever seen, and after hearing how they spoke to each other, it's little surprise.
Arsene Wenger and Jose Mourinho were two completely different personalities meaning and with them leading two of the biggest clubs in the country, it was always a rivalry that was ready to ignite.
Arsenal were the dominant force in the top flight when Mourinho arrived from Porto in 2003 claiming to be 'the special one'.
While that famous quote rubbed plenty of people up the wrong way, Wenger responded particularly badly.
He said: "He's out of order, disconnected with reality and disrespectful. When you give success to stupid people, it makes them more stupid sometimes and not more intelligent."
We all know Jose Mourinho and how he operates, but the then-Chelsea boss didn't shy away from such comments from one of the longest-serving Premier League managers, instead opting to put him in his place.
Replying to Wenger's comments about Chelsea's spending power, Mourinho said: "They go season after season getting players like [Thierry] Henry, [Patrick] Vieira and [Jose Antonio] Reyes.
It's a big surprise to me if Seville gave Reyes for free as a Christmas gift. Reyes last Christmas was quite an expensive gift."
This exchange was only the start of a rivalry that would go on throughout Mourinho's two spells with Chelsea and his time at Manchester United.
Of course the rivalry seemed to come to a head when Jose Mourinho described Wenger as 'a specialist in failure', which understandably did not gone down too well.
But while they may have appeared to be rivals, but deep, deep down there's bound to be an underlying respect between the two.
