Gameplay, Hecarim knockback animation

I recently played a game as ezreal. When the opposing hecarim jungle ganked my lane, I used my e just before he knocked me back, but the animation showed me getting knocked back half a screen away from where hecarim ended up using the skill. Should hecarim follow or is the charge avoidable or should the effect simply take effect before ezreal's dash away? This question assumes the current outcome is not the one which was intended. Hope this helps get it fixed, thanks :-)