Search pics of bahiagrass and see if that's your guy. Hesitant to suggest that though if you haven't seen blooms. They bloom so fast even the "good yards" around here get full of the tall flowers sometimes. The seeds form apparently overnight and get all over your legs, shoes, pants, feet...

First contact your local office of the Clemson USDA Cooperative Extension Service and the can help identify that and can also help you get a good, reliable soil test which might do as much to control this as anything else. Many "weeds" grow in soils that are not good soils for turf grass and turf grass most often needs a good, healthy soil or it will not grow well. At the same time dig in with these simple soil tests, Structure. From that soil sample put enough of the rest to make a 4 inch level in a clear 1 quart jar, with a tight fitting lid. Fill that jar with water and replace the lid, tightly. Shake the jar vigorously and then let it stand for 24 hours. Your soil will settle out according to soil particle size and weight. A good loam will have about 1-3/4 inch (about 45%) of sand on the bottom. about 1 inch (about 25%) of silt next, about 1 inch (25%) of clay above that, and about 1/4 inch (about 5%) of organic matter on the top. 2) Drainage. Dig a hole 1 foot square and 1 foot deep and fill that with water. After that water drains away refill the hole with more water and time how long it takes that to drain away. Anything less than 2 hours and your soil drains too quickly and needs more organic matter to slow that drainage down. Anything over 6 hours and the soil drains too slowly and needs lots of organic matter to speed it up. 3) Tilth. Take a handful of your slightly damp soil and squeeze it tightly. When the pressure is released the soil should hold together in that clump, but when poked with a finger that clump should fall apart. 4) Smell. What does your soil smell like? A pleasant, rich earthy odor? Putrid, offensive, repugnant odor? The more organic matter in your soil the more active the soil bacteria will be and the nicer you soil will smell. 5) Life. How many earthworms per shovel full were there? 5 or more indicates a pretty healthy soil. Fewer than 5, according to the Natural Resources Conservation Service, indicates a soil that is not healthy. to learn more about the soil you have and what yo need to do to make that soil into something that will grow a good, healthy turf. Here is a link that might be useful: Clemson CES

Another option is Gordon Ornamec 170, it's cheaper than 2 bottles of the Bayer and will last you many years. It's also good for other tough weeds like quackgrass and dallisgrass. https://www.amazon.com/Ornamec-170-Herbicide-32-oz/dp/B008MZQE6O/ref=sr_1_1?ie=UTF8&qid=1470488280&sr=8-1&keywords=ornamec+170 Yes, you will need to apply a pre-emergent. I recommend prodiamine, it will control this and most other weeds.

I believe I have correctly identified this as orchardgrass.