Manchester United teenagers Amad Diallo and Shola Shoretire are set to feature against Leicester with fixture congestion making it "impossible" to field a full-strength side, says Ole Gunnar Solskjaer.
United can close the gap on Premier League leaders Manchester City to four points if they win their two midweek games, but fitting four matches into eight days leaves Solskjaer with no option but to rotate against Leicester and Liverpool.
"I wish I could have said, 'Let's go full out in all the games,' but it's impossible," said Solskjaer ahead of Tuesday night's visit of Leicester.
"That's the hard bit for me, knowing that if I do play this same 11 on Tuesday and on Thursday it's impossible.
"I run too much of a risk of injuring them, so talking about integrity in the league and stuff, don't blame me when I have to make changes because I have to. It's not safe for them to play all four."
It could mean a Premier League debut and first United start for Amad, who arrived at Old Trafford in January from Italian side Atalanta after signing in the summer for an initial £18.7m.
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United academy product Shoretire made his Premier League debut against Newcastle and is also yet to start for the first team.
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"They are in contention," Solskjaer said of the pair. "They are in the first-team squad, they are training with us every day.
"I would think that some of the young boys will get an appearance definitely. If it's coming on towards the end or from the start I don't know because I don't know how the players will be on Tuesday when we see them."
'Greenwood's got something special'
Mason Greenwood's second-half goal at Villa on Sunday, which proved to be the winner, ensured he overtook Wayne Rooney's record to become United's highest-scoring teenager in Premier League history.
Solskjaer was full of praise for the 19-year-old, who had been suffering from a goal drought earlier in the season, but has now scored six in his last six domestic matches.
"Mason is learning all the time, he's learning on the job, and it's difficult, he's had to bear a lot of responsibility, and he's popped up and scored a lot of important goals for us," added Solskjaer.
"Thursday night, he worked his socks off and he goes again. He's tired, his body's not really filled out yet and he might not be ready for all these games but he's got something special.
"The kid just turns a game around in one split second and the goal today was excellent. I'm delighted that he's got back to his goalscoring best and he's learning more and more all the other bits."