When a shooter runs off a down screen or a stagger, his defender puts a hand on the cutter’s hip and follows him over the top of every screen, staying on his back the whole way. He is never in front and never behind, just attached. The idea is that the shooter can catch it, but not catch it and shoot it.
You will hear this called chase, trail, or lock and trail. They are the same coverage.
Why coaches use it
It is the honest answer to a shooter you cannot leave. Top-locking him gives up the backdoor, switching gives up a mismatch, and going under gives up the shot. Chasing gives up nothing on the catch as long as the defender does not get held up on the screen.
It is also the coverage that most depends on the screener’s defender. If he does not bump the cutter or open up a path, the chaser is stuck on a body and the shooter is free.
How to attack it
- Curl it. A defender on your hip cannot follow a tight turn. Curl into the middle of the lane and either finish or find the man his help left.
- Use a second screen. A stagger gives the chaser two bodies to fight through, and he is already a step behind after the first.
- Screen the screener. A defender chasing over the top has his back to the floor. That is the moment to screen him.
- Change speed. Walk your man into the screen, then sprint. A chaser who is moving at your pace never gets caught.
In the product, this is the off-ball screen setting called Chase, next to Top-lock, Under and Switch. Flip between two of them on the same drawn set and the shooter’s best cut changes.