Ole Gunnar Solskjaer on Friday defended the professionalism of Mason Greenwood, saying the "whole English press" have targeted the Manchester United forward after he was sent home from England duty last month.
The 19-year-old has made a big impact at Old Trafford since making his first-team debut in March 2019, scoring 17 goals last season and recently making his international debut.
Greenwood was sent home from his first England camp for breaching coronavirus protocols in Iceland and he has reportedly been warned about his behaviour, including his time-keeping, by the club.
But Solskjaer, speaking at his pre-match press conference on Friday, brushed that issue aside as the teenager prepares to make his return against Chelsea this weekend.
"You do (make a target for yourself) when you play well and I'm not concerned at all with Mason making a target of himself," said the United boss.
"He's come in, he's played fantastic, he played his first league game against (Arsenal) last season, was brilliant and just kicked on.
"Yeah, he's made a mistake this summer with England and suddenly the whole English press go after him and that's something we've got to look after."
Solskjaer described Greenwood as a "fantastic boy to work with".
"I have to disappoint you, he's never, ever late for training, he's never a problem when he's in the training ground," he said.
"He's always on time. I've seen the stories, actually some ex-United players talking about him and they don't really know anything what they're talking about because, well, we've got photographers outside the training ground every day so they can check the time every day."
The Norwegian boss added: "He's a good trainer, he trains really well, and I cannot believe all these stories about him not being professional."
Greenwood missed United's impressive Champions League win at Paris Saint-Germain on Tuesday with an unspecified issue, while captain Harry Maguire and new signing Edinson Cavani were other high-profile absentees.
Solskjaer said he expected all three of them to be available for the visit of Chelsea on Saturday.