Jose Mourinho is arguably one of the greatest managers ever, but even one of his former Chelsea charges found the Portuguese boss an infuriating genius to work under.
The Special One, The Happy One, and The Chosen One - all nicknames Mourinho has dubbed himself - has worked at a range of different clubs during his career, working with some of the best players to grace the game and winning countless trophies.
And while his man-management tactics have clearly worked, it often frustrates players, too.
Indeed, Demba Ba played under Mourinho for 18 months at Chelsea, in the 2012/13 and 2013/14 seasons. The Senegalese striker struggled to have the same impact on the Blues as he did during his spell at Newcastle United, though, having to share playing time with Fernando Torres and Samuel Eto'o.
Regardless, when Ba reflects on his time working with the Portuguese boss, he is clearly still enamoured about the impact Mourinho could have.
"Some days you want to hit his head against the wall, but then you leave and think, ‘That’s probably one of the best managers ever’. It’s crazy," Ba tells FourFourTwo.
"He has the ability to play with people’s emotions to get what he needs out of them."
Ba ultimately ended up growing tired of the mind games Mourinho would play at Chelsea, though, leaving for Besiktas in July 2014. Having already spent time in France, Belgium, Germany and England during his career, the striker wanted to play his football in a new country.
"I’d like to have stayed at Chelsea. Jose asked me to stay, but at that point I was tired and didn’t want to fight against him for another year. The opportunity to go to Turkey came up and I grabbed it.
"As a Muslim, I wanted to experience the lifestyle, as well as the intense atmosphere in the stadiums. The passion is different. For big games, the ground might be 80 per cent full when the team bus arrives."
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