Sudden jump in difficulty?

So I'm an average-ish player, get to around rank 10 regularly these past few months. I was away from playing just for a week or so, and I wanted to test my decks on casual just to see how they're doing against the new cards. But I find I'm getting destroyed there. Without exaggerating, I'm 1-10 out of these past matches, even when switching decks which were all viable. Has anyone else noticed a big jump in difficulty lately?