They are two of the most successful managers the Premier League have ever seen - and their feud is almost as legendary as their results.
Once upon a time Pep Guardiola and Jose Mourinho were friends and worked well together. However, as both strive to better the other, it's fair to say those days are long gone.
Back in 1996, Mourinho was employed by barcelona as Bobby Robson's translater while Guardiola was still playing for the club.
The manager described the two men as "quite friendly" while Guardiola himself described it as a "working relationship". Even after Robson left, Mourinho stay on and worked under Louis van Gaal for another four years.
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