Where are you seeing the fuzziness? Your version is full of jpg artifacts (like any compressed picture containing a lot of red).
On literally the whole thing; it all looks slightly out of focus. I think I found out why, too: both resized versions are jpgs, but the other is the full 850px while this one's only 849px, and then stretched to 850px on this page. If you right-click this one and open it in a new tab, you'll see that it's much sharper than what you see on the page. (But you're right, if you look at the original images there is a bit of artifacting in the other I didn't notice before, so this one should be the parent.)