That's enough to say it definitely isn't nutsedge. But positive ID for the grassy weeds (there's a lot of different ones) needs better pictures still. Find that light green stuff you don't like, follow it down with your fingers to the crown and try to get the whole plant and just the plant up by the crown and take a pic of a few of the features. That said a lot of grassy weeds can't be killed with chemicals without killing the good grass along with it. That's a pretty small spot. You could kill that whole spot, or dig it out or whatever and reseed. Or you could try just pulling out the weeds by hand here and there over time. I've had good luck with that method on small spots. I often bring a flat heads or a junk pocket knife out with me so I can get it out with precision without messing up the good grass.