Manchester United were left outraged by Brentford’s opening goal at Old Trafford on Saturday afternoon. The visitors took the lead through Ethan Pinnock on the brink of half-time after Manchester United were reduced to 10-man for a last-gasp corner. Matthijs de Ligt was forced to the sidelines for treatment of a head injury and Brentford capitalised while United’s £38m summer signing was out of action. De Ligt was pictured reacting furiously on the touchline after he had to sit and watch United concede. Thankfully, Erik ten Hag inspired his side to a second-half comeback with Alejandro Garnach…