Bill Hayes, Shorin Ryu, on Shuto Uke

It needs to be more than just a block/parry to a strike.

 

It can be first a block/parry to a striking arm.

 

Then completing the technique as a strike into the neck to disable the attacker.

 

slightly different variation.

 

Under no circumstances try to block/parry the arm while moving back.   They can advance faster than you can retreat.