Sure looks like grabgrass to me. Here's a fairly organic fix. Spray the leaves with water mixed with a non-ionic surfactant (a few drops of non-antibacterial dish soap will work). Once thoroughly wet, fill an old sock with baking soda and beat it on or above the plane so that the dust gets on the leaves. They'll be black within a few days. Some of the leaves may not die so hit them again in a week or so. This will also kill the beneficials in your soil (thus the above reference to a fairly organic solution). Onve you're done treating throw some compost or compost tea on the areas to get the count back up.

BTW, how's the orgainc going on the Bermuda. I'd love to try it, but I don't have a good local source for feeds.