So I'm watering too much?
Not sure how much are you watering?
It could be an area that just doesnt dry out quickly.
It has never been a problem for me growing or extablishing grass in areas that look like that.
Its impossible to diagnose from pictures. I dont want to tell you your over watering when that could be just an area of you lawn that gets overlapped by sprinklers.
Do you know how much water you apply every week?
If your answer is I run my sprinklers for ( blank) minutes than you dont know how much water you putting down.
Set out some empty tuna cans or cat food, run the sprinkler for 15 min and then measure how much water is in the tuna can.
Thats how much water you put down in 15 min.
For most grasses you need at least 1 inch of water every week.
If you start having run off because your watering for such a long period of time then break it up. Water for 10 min let it soak in and then water another 10 min and so on.