“I went to this game and there were a number of worthy performances in defence for Liverpool on the night but Joel Matip was probably the most notable for me," Crooks told BBC Sport.
“Matip wasn't the least bit concerned about the threat from Diego Costa. In fact, in the first half it was Matip who consistently and quite deliberately gently nudged Costa in the back, causing the striker to miscontrol the ball.
“It's a trick clever defenders employ in order to stop the striker from setting the play, and it often goes undetected by the referee as it appears as though the striker's control is poor.
“Why such dark arts should thrill me on this occasion I'm not entirely sure. I suppose anything done well should be applauded."