In games like this you definitely feel the absence of Chiellini. Petagna is able to control the ball too often and keep the pressure off his team. Chiellini would be more aggressive than De Ligt and Bonucci and would often win the ball with the first challenge instead of allowing to control the ball for a couple of seconds, giving SPAL time to regroup. Obviously not the main issue right now, but just pointing out how sorely missed Chiellini is.