Ole Gunnar Solskjaer said Rio Ferdinand was "out of order" with his comments on why Phil Jones is still a Manchester United player.
Defender Jones, 29, has not played a Premier League game since the 2-0 win over Burnley on January 22 last year.
Former United star Ferdinand said on his Vibe with Five video that Jones should have been released "ages ago" and suggested he was unfairly keeping youngsters out of the first-team picture by being at the club yet unavailable.
The centre-back has been struggling with long-term injury issues, the most serious of which is a knee problem, but he played his first United game for 18 months in a behind-closed-doors friendly last week – also against Burnley.
Solskjaer, who himself battled a long-term knee problem as a player, explained on Friday why he has not been prepared to rush Jones back into action.
"Phil has had a horrible 18, 19, 20 months and probably a year before that as well with injuries," he said. "I think Rio was a bit, not out of order, he should have called me and asked why Phil hasn't played or why Phil hasn't been here.
"Phil is a no-fuss, get-on-with-it type of guy, and I think that was out of order completely [from Ferdinand]. I know more than anyone how it feels to be injured.
"Phil is still not 30 years of age. Since I came back here, he's battled against his knee injury and he put his body on the line every single training session, every single game. There are a few times we've had to manage him, and he's never done anything but give everything for the club.
"Rio of all should know more than go out and say this. I wanted to say a lot, I've not said a lot about Phil's injury because I protect him, he never does social media, never has to do interviews, just gets his head down, proper professional, no fuss, a family man, and just wants to get back fit.
"I was out for two years in a three-year period with a knee injury and Phil has battled valiantly and I know how Phil has felt. Because you're embarrassed at times coming in, but he has to look after his career and he's now getting back to fitness.
"Now is not the time for me to throw him in. Maybe give him a little more, a month, six weeks and he'll be there. For me as a manager to see he can see light at end of the tunnel, it's great because I've been through the same."
While Jones appears unlikely to leave the club before the transfer window closes, there remains speculation over the future of Jesse Lingard, but Solskjaer seems keen to keep a player who has just earned an England recall.
"I know there's loads of speculation about him, but he's had a very good pre-season; just been picked for England in the squad," he said.
"It's just been unfortunate that he got COVID just before the league started. He would have 100 per cent started the first game [against Leeds United] because of the pre-season he had, so I can see him doing well this season."
Solskjaer also insisted Donny van de Beek will be given his chance to impress this season, even though he did not get off the bench in United's opening two fixtures.
"We started against Leeds with a 5-1 win, [which was] justification for the team selection," he said. "Then we moved to the next one, Scott [McTominay] couldn't play and Nemanja [Matic] has been our best player in pre-season.
"Donny has worked hard, he's done really well, I can't say anything else. He'll get his chances when the season gets going."