Raven vs Woodpecker

We have a pair of ravens residing nearby and have seen them chasing crows and jackdaws from their territory however the other day one swooped down and chased a woodpecker (greater spotted) off one of the birdfeeders and pursued it with what I can only describe as great intent. I have heard woodpeckers can be aggressive especially at this time of the year but surely no match or concern for a raven Can anyone shed any light on this please?