He's always going to have some success. Can't shut him down completely. Have to double him, but in creative ways. Some defenses will do things like match him up man to man with a linebacker, but then the linebacker peels off at 5-10 yards and goes into a zone. Then a safety, who played zone off the snap, comes up to fill in the man coverage. That can create a risky window during the trade off, but it can also bait throws that look open, but have a robber coming in to pick or break up the pass.
What worked once will generally not work all game though, so there have to be multiple plans of attack and adjustments in the bag ready to be pulled out on the fly. I'm hoping to see those type of adjustments this year and see that Rex is the guy who can do those things, take away other team's strength's to make them have to adjust, etc.