A disagreement over tactics was the beginning of the end to Iker Casillas' illustrious career at Real Madrid. In Mourinho's eyes, Casillas could do no right and was eventually dropped to the bench before moving on to Porto.

On the heels of being named Chelsea's player of the year in 2013, Juan Mata only lasted half a season upon Mourinho's return to Stamford Bridge. The Spanish midfielder was consistently left on the bench during Mourinho's second spell, as the Portuguese gaffer was reluctant to find a place for Mata in his system before shipping him north to Manchester United in January 2014.

Suspicions over Samuel Eto'o's age have lingered for much of the Cameroonian striker's career. But it never appeared to faze the striker until Mourinho was caught in a secret recording saying, "I have Eto'o but he is 32 years old, maybe 35, who knows?" That didn't go over well with Eto'o, who acknowledged the comment with his infamous "old man" goal celebration.

The relationship between Mourinho and William Gallas was so toxic that Chelsea released a statement claiming the French defender had threatened to score own goals after he was shipped to Arsenal in the deal for Ashley Cole.

The feud with Mourinho started when Pepe came to Iker Casillas' defence, with the Portuguese defender claiming that his compatriot's criticism of the goalkeeper was not adequate. Then Mourinho got personal, insisting Pepe's anger stemmed from the fact that he was on the verge of losing his place in Real Madrid's first team.

The rift between Diego Costa and Mourinho didn't last long, but it sure was dramatic. Their feud started with Mourinho voicing his displeasure with Costa's fitness, which led to the Spanish striker getting dropped to the bench. The situation boiled over when Costa tossed his training bib in Mourinho's direction as he took his seat on the bench.

Perhaps the most puzzling case of a player to clash with Mourinho involves Anthony Martial. The latest, most bizarre incident occurred during United's preseason tour of the United States, when the French winger left the team for the birth of his child as Mourinho moaned about his absence. He even threatened to fine Martial, who, for some unknown reason, is still a Red Devil.