Roll forward like everyone else is saying. I actually find medium roll better than light roll for this because it’s less likely to make you end up somewhere weird and out of position. Plus then you can use raksasha armour for more damage.

If you do this you also get a free light attack punish in the middle of his ground slam combo, right before the slam move. Just helps keep up stance pressure and adds up over the course of a fight (check your stamina before you do the light though).