Read a couple of articles about him on The Athletic today. 1 said when he was at Chelsea he mainly stayed in the penalty box and didn't have much space to defend. Which seemed to suit him a lot more than how Arsenal are (or were seeing as that was probably his last game for them) trying to play him. Also aside from Luiz the most penalties caused this season by individual players in the PL is 2. Luiz has caused 4.