Deablo (forearm) was downgraded from doubtful to out Saturday ahead of Sunday's clash against Kansas City, Tori McElhaney of the Falcons' official site reports.
Deablo suffered a forearm injury in Week 6 against Chicago and missed Atlanta's subsequent two games. He returned to face the Bengals last Sunday but apparently aggravated the issue, and he didn't practice Thursday or Friday this week. With Deablo now ruled out against the Chiefs, Harold Perkins should get a healthy dose of defensive snaps at linebacker.