Mudryk was absent from training this week at the club's facilities in Cobham and it has now been revealed that he has suffered an injury.
In a post on their official website, Chelsea confirmed that the Ukraine international is undergoing treatment.
On an injury list of eight other players, Mudryk's name has been added and said: "Starting rehabilitation having undergone assessments on an injury sustained in training this week."
Blues coach Pochettino gave some information on the injury, though was coy but insisted the problem is hopefully minor.
He said in his press conference on Thursday: "A few days, but he won't be available for tomorrow.
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"He is a player we hope to help him perform in the way we believe he can perform. It is not a big issue, we need to wait one week or maybe a few days."
But it adds to yet another headache for Pochettino, who is losing players almost by the day.
Carney Chukwuemeka will miss six weeks of action after suffering a knee injury against West Ham on Sunday, which forced him to undergo surgery.
Reece James, who has been appointed Blues captain, could be out for months after an injury in training last week.
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And star signing Christopher Nkunku could miss the rest of the calendar year with a knee injury picked up in pre-season.
As well as the named quartet, Armando Broja, Trevoh Chalobah, Benoit Badiashile, Marcus Bettinelli and Wesley Fofana are all currently sidelined.
Only one other club in the Premier League has more injuries at the moment, behind Sheffield United.
Mudryk has had a tough start to the season after ending up on the bench for both openers against Liverpool and West Ham.
After coming on against the Hammers, the 22-year-old proved ineffectual despite them having 10 men.
Chelsea lost 3-1 to their London rivals on Sunday as a result, leaving them with one point after two games.
Pochettino will hope for better fortune against Luton on Friday night at Stamford Bridge but will also be praying for no more injuries.