Oh, these could possibly be from the grounds keeper applying fertilizer and or seed, with a circular spreader. We had very similar circles on our lawn, after my husband and father in law messed around with “lawn maintenance” years ago.
The thing, a push spreader, with a circular drum, had to be in constant motion, otherwise spots, like in your photos, would get extra fertilizer spread in a tight circle.
Thanks. Actually I didn't see that someone used this spreader there. I got what you mean.
It is football court, i asked guys who play football there, they said that it was before, but they look at me like " I'm from another planet")
Then I asked the friend of mine, and I showed him this thing, he said that he saw smth similar at another place. I don't know if it is the same thing.
Maybe I too much into observing what is going on around, but Too much strange stuff Is happening from my view of perspective.
Nevertheless, I will try to find out if there was this spreader.