If you want to know why referee Paul Tierney sent off Rob Holding in last week’s north London derby then head out into your garden and run headlong into the bird table.
That is precisely what it must have felt like for Tottenham’s Son Heung-min.
Running on to a through pass from deep, Son was felled when Holding slowed his run, half-turned and held his forearm out at head height. It was a pre-meditated, deliberate act and could easily have been punished by a straight red card. Instead, Tierney presented a second yellow and Holding walked.