The Tottenham boss has been the subject of praise.
The north London side host their Serie A counterparts on Thursday night, having drawn the first leg of their tie 1-1 in Italy.
And Sousa is quoted as telling reporters: "First and foremost Mauricio's mentality and approach is one of someone who always wants to win.
"I find it hard to imagine a manager going into a game thinking they don't want to win or not being interested in winning a competition. And you can't just focus on one competition.
"You have to bear in mind that Mauricio comes from a very competitive footballing background and certainly he will want to win."
As ever, though, the Thursday-night competition doesn't necessarily go hand in hand with a Premier League title challenge - or at the very least an attempt to ensure finishing in the top four.
Tottenham will no doubt go for it against Fiorentina but it's easy to envisage Pochettino resting one or two big names. Spurs host Swansea City on Sunday afternoon and, despite the Swans hovering near the relegation zone, no league clash is easy - especially three days after a European game.