Just noticed a fungus in my lawn

I have what I'm pretty sure is zoysia in some partial shade areas of my back yard. The last couple of days it started looking like it was suffering from a drought or something. Took a closer look yesterday.



Applying this to it after work. From what I've read it's zoysia patch and this should stop it.





Anything else I should do? How long will it take to recover from this? Ignore the torn ends. After the storm last week I put some old blades on my mower to mulch all the leaves/twigs. Sharp blades are going back on it soon.

This is mixed in with st aug. It doesn't look like it has been affected yet.