Despite denying rumours that Mason Greenwood has been absent because of disciplinary issues, Ole Gunnar Solskjaer is believed to be furious with the talented young forward.
The 19-year-old enjoyed a remarkable 2019/20 campaign for the Red Devils, but has been involved in a number of off-field issues of late.
Greenwood was first kicked out of the England camp after he invited girls over to his hotel room with Phil Foden, and has since fallen out of favour at United, reportedly due to discipline problems.
According to The Sun, Solskjaer has been left frustrated with the forward's recent behaviour after reports suggested he arrived late for training on two occasions.
Greenwood missed United's recent away trip to Newcastle United in the league, while he was also left out of the squad for the team's 2-1 win away at Paris Saint-Germain in the UEFA Champions League.
It has been claimed that Greenwood had been caught drinking before a recent game, but Solskjaer insisted he was absent due to a niggle.
The young attacker has scored 18 goals in 57 senior appearances for the Premier League giants, assisting a further six strikes.