Devilgrass is another name for common Bermudagrass. This definitely would be a problem in hybrid Bermudagrass. Unfortunately, there's no option other than to spray the infested area with a nonselective herbicide such as glyphosate (Roundup), which will kill everything, then reestablish the hybrid Bermuda-grass. One way that common Bermudagrass (devilgrass) spreads is by stolons that are carried around on mowing equipment. Bits of devilgrass stem can fall from the lawn mower blades to the soil, develop new roots, and start a new colony. After you get this area under control, be sure that your lawn mower is not being used on other lawns that may have a devilgrass infestation.