Mourinho has a long and storied history of picking out individuals in his squad to single out for motivation, with his Portuguese countryman the latest candidate.
Since his very public fallouts with Iker Casillas and Sergio Ramos at Real Madrid, Mourinho has used huge names such as Paul Pogba and Dele Alli to set the standard in his squad.
The most brutal of all, though, was Luke Shaw while at Manchester United, with one report from inside the dressing room accusing him of 'bullying' the left-back due to a perceived lack of fitness.
He's now angled a similar criticism at 26-year-old Sanches, for issues keeping him out of the line-up.
Speaking in a press conference, Mourinho said: "Renato Sanches and [Houssem] Aouar? They both need to play and find their rhythm.
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"Unfortunately this is Renato, he is always at risk [of injury]. It's difficult to understand, Bayern [Munich] didn't understand it, PSG didn't understand it and we don't understand why either.
"He had three days of preparation, he was fine but he felt something."
Sanches is perhaps best known among English audiences for his time at Swansea during the 2017/18 season.
Graduating from Benfica's academy and starring at Euro 2016 for a victorious Portugal, Bayern Munich won the race for the €80million youngster, but it never worked out.
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He later left the Bavarians for French side Lille where he rediscovered his form and won the league title in 2021, before being bought by PSG and doing the same.
Loaned out by the Ligue 1 champions this season, Sanches has only 98 minutes to his name since joining, which coincides with Roma's poor league start of one win in four games.