Looks like agave borer weevil damage.

This is in Arizona near Tucson, BTW.

Ya that would be my guess too:(. There’s a real problem with those in Arizona. They have them in So Cal, but haven’t made their way up here yet. Hopefully they never will.

Why the strong rusty stain, I wonder? Looking at examples of borer weevil damage, the wrinkling or shriveling looks the same, but none have that rusty tinge.Could it be something else on top of the borer damage?

The rusty stain is likely the 1st signs of rotting. It will turn dark brown/black in time. I would tug on the plant to see if it starts to separate. If so, I would remove it and be sure to kill all the grubs you find.

Thanks, all. I found a video on youtube that shows similar discoloration:

https://youtu.be/uxY5213CP30?t=6m5s

Here's a Christmas pic from Tucson