It was just a chain reaction caused by not being ready to defend with 10 men. Kulusevski goes wide, not really thinking that he should probably stay more central since Berna is not on the pitch. Then Alex Sandro DOES come out of defence to try to fill that hole left by Kulu. Then that causes Locatelli to think about covering Alex Sandro, because he left a gap there. And then that gives Calhonaglu a bit of a lane.
