Leather jackets?

Hi all,

I am new to gardening and my lawn has been dying since we moved in last summer (granted we didn’t mow or water the lawn at all as we didn’t have anything to do this with for a while) but are now keeping on top of it.

The lawn has been getting mossier and mossier and yellow dead patches everywhere. I’ve been reading about leather jackets and wanted to know if anyone can confirm whether this is a leather jacket pupa? I did squish it (sorry). I notice there are holes in the mud beside it but basically this was what was underneath a bit of moss I pulled back.