Trent Alexander-Arnold not happy after being substituted on 72 minutes of Liverpool's 2-0 win over Brentford... as boss Arne Slot says he understands his frustrations 

Liverpool breezed past the Bees 2-0 after goals from Luis Diaz and Mohamed Salah - but fans quickly noticed Alexander-Arnold's gloomy expression when he was taken off midway through the second half.