The former Chelsea defender has highlighted what makes the current Stamford Bridge boss so successful.
The title is their fourth in nine years, but also their first in five years, and Desailly says the Portuguese boss deserves credit for turning his side into champions this time around, highlighting just what he does that is so special.
"The ability of Mourinho is, first of all, the ability to choose players who fit the exact profile of what he requires and, secondly, to control the squad," he said.
“There has not been a single internal controversy, and each and every second-choice player, when called upon to do their job, have done very well. This is where Mourinho is very good.”
The former defender has also praised the flexibility within the squad, with several players able to play in a number of positions.
For example, Brazilian midfielder Ramires has played in central midfield and out wide, Kurt Zouma has been both a central defender and a defensive midfielder at times, and full-back Branislav Ivanovic is comfortable playing at centre-back as well.
And Desailly says that makes the current side better than the one from 2004/05, which he says relied more heavily on exceptional performances from the likes of Didier Drogba.
"There is a greater diversity of the players now," he added.
"If you look at Ramires, he can play as a winger or as a defensive midfielder; Branislav Ivanovic can play as a centre-back or a full-back; Kurt Zouma can play in defence or as a defensive midfielder. If you look throughout the squad, all these players are interchangeable, it's just amazing."