Chelsea’s failure to promote from within their own ranks has been well documented, with John Terry – whose debut came back in 1998 - being the last academy graduate to make a real impact on the first team.
The Blue's FA Youth Cup success in recent years, winning the competition in three of the last four seasons, has offered cause for optimism and chief among that promising bunch is Ruben Loftus-Cheek.
Mourinho was sufficiently impressed by the powerful, elegant central midfielder to grant him his first-team debut last December in the Champions League and three additional Premier League appearances. It would appear as though their relationship has become strained, however, following Tuesday’s lacklustre performance.
“Ruben said he had a pain in his back but what I was feeling was that he only had the pain when Sydney had the ball,” Mourinho told the club's official website.
"When Chelsea had the ball he was playing very well, but when Sydney had the ball I think he was more impressed by watching Matic and Mikel work, instead of him working.
"So, with Ruben, it’s one step back in terms of my relationship with him. If he doesn’t know what it is to play for me and Chelsea it’s one step back."
Mourinho is forthright in his appraisal of Loftus-Cheek’s abilities but has question marks over his commitment to working off the ball and replaced the Chelsea man just 28 minutes after he had been introduced as a substitute.
“He has to learn that at 19 you have to run three times more than the others, you have to play to your limits and not play like a superstar with the ball at your feet because this is not Under-18s," added the Portuguese coach.
"I don’t accept that in the superstars so how can I accept that in a kid? He has to learn what it takes to play for us."
Loftus-Cheek was expected to be an important member of the first-team squad next season, but after Mourinho's comments such a standing now seems a long way off. The Chelsea manager, and fans alike, will be hoping those harsh words spark a reaction from Loftus-Cheek in the remainder of pre-season.