Manchester United have recorded a number of positive Covid tests among players and staff following their 1-0 win at Norwich on Saturday.
The club has reported the cases to the Premier League and their match at Brentford on Tuesday is now in some doubt.
It is understood that all players tested negative before the Norwich game.
But a number of players tested positive before training on Sunday morning.
Those individuals were then sent home and training was adjusted to individual and non-contact sessions.
Aston Villa also had one positive Covid case on Sunday, which meant that an indoor recovery session was cancelled as a precaution rather than have members of the squad recovering inside the training complex at Bodymoor Heath.
It is understood that if a full training session was taking place outside it would have gone ahead as normal.
This weekend’s Tottenham v Brighton game was postponed after an outbreak in the Spurs squad.
And in the Championship, Sheffield United’s match against QPR on Monday has been called off due to an outbreak in the QPR squad.