diff --git a/KnifeRevert/scripting/KnifeRevert.sp b/KnifeRevert/scripting/KnifeRevert.sp
index df54737..ec1132a 100644
--- a/KnifeRevert/scripting/KnifeRevert.sp
+++ b/KnifeRevert/scripting/KnifeRevert.sp
@@ -117,7 +117,7 @@ public Action OnClientKnife(Handle timer)
 
 public void ZR_OnClientInfected(int client, int attacker, bool motherInfect, bool respawnOverride, bool respawn)
 {
-	if(!g_bKnifeRevert || !g_bKnife)
+	if(!g_bKnifeRevert || !g_bKnife || attacker == -1)
 		return;
 
 	if(g_iClientIndexKnifedZombie == attacker)//originally knifed forward zombies kills ppl