You should get this within the first 15 minutes of the game but it can be unlocked during any fight. Simply get your sword knocked out of your hands by blocking a heavy attack from an enemy, and then roll away from your sword by pressing any direction,
. Now, roll back in the direction of your sword using the same buttons as you used before, but this time as you’re rolling over your sword, press
to pick up your sword and the achievement will unlock.