Manchester United defender Chris Smalling has a broken toe which will rule him out for up to four weeks, according to Sky sources.
If confirmed, the 26-year-old looks set to miss the Old Trafford showdown with Arsenal on November 19, live on Sky Sports 1.
Smalling missed the 3-1 victory at Swansea last Sunday and it is understood he aggravated the injury during a light training session earlier this week.
The centre-back and fellow England defender Luke Shaw appeared to be the subject of Jose Mourinho's disapproval after the Swansea win when the manager argued there are those who are brave and "ones for whom a little pain can make a difference", adding you have to "go to the limit".
The questioning of the players' pain threshold would suggest the duo were only suffering minor issues but it now seems Smalling may be on the sidelines until after Christmas.
Gareth Southgate left both United defenders out of his squad for Friday's World Cup qualifier against Scotland and Tuesday's friendly with Spain, saying there was "obviously something wrong" with them.
"Obviously it's a difficult one because I don't know the reason for the comments Jose's made," Southgate said.
Former Celtic striker Andy Walker told SSNHQ he thought Mourinho was trying to force Smalling and Shaw out of the club, while Professional Footballers' Association chief executive Gordon Taylor expressed his disappointment with the United manager's public criticism.
On Mourinho's comments, Gary Neville, who worked with Smalling as England assistant boss, said: "Having worked with [Smalling] for four years he has always been incredibly impeccable and trustworthy, someone I always felt would run through a brick wall, so I am surprised."
Smalling last featured in United's 4-0 drubbing by Chelsea on October 23 and has featured in seven of the team's 11 Premier League games this season.
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Mourinho is already without centre-back Eric Bailly until Christmas with a knee injury, while right-back Antonio Valenica has undergone surgery on a fractured arm.
Watch Manchester United v Arsenal, live on Sky Sports 1, Sunday November 19 from 11.30am