Mourinho began coaching Rashford at Old Trafford following his appointment as Red Devils boss back in May 2016.
Rashford found himself playing second fiddle to Zlatan Ibrahimovic for much of last season but still produced some crucial goals for the Red Devils as they won an EFL Cup and Europa League double.
The 19-year-old will be hoping to hold down a regular spot in the first team at Old Trafford next season as Mourinho prepares for his second season in charge at the club.
And Mourinho feels that Rashford has already developed physically as he prepares for his second campaign.
Speaking at his post-match news conference after Manchester United’s 5-2 win over LA Galaxy on Saturday night, Mourinho said: “It’s just the natural evolution of a kid.
“You change your body when you’re a young kid. He’s already taller than when I arrived 13 months ago – he’s three centimetres taller – and he put on some muscle but without any kind of specific work because his speed is his most important quality.”
Manchester United are preparing for a return to the Champions League next season after they won the Europa League last term under Mourinho.
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