If you can limit the space Salah has he is largely ineffective, always found that to be the difference between defending against him and defending against Hazard. Hazard could leave you for dead over 2-3 yards of space. Salah, Martinelli, Greenwood, Son, Kane and Ronaldo are probably the worst players to come up against if you give them space to operate.
If you look at the passmap it makes it quite clear: he wasn't getting the ball anywhere near as much as expected, and when he did get it he was sending it back to Keita - which says that Sessegnon and Davies were keeping him quiet That being said, Salah's heatmap is more interesting... please log in to view this image