diff --git a/Source/Core/Map/Thing.cs b/Source/Core/Map/Thing.cs
index 7105fb4c..fd37bf52 100755
--- a/Source/Core/Map/Thing.cs
+++ b/Source/Core/Map/Thing.cs
@@ -283,7 +283,7 @@ namespace CodeImp.DoomBuilder.Map
 			{
 				sector = null;
 			}
-			if (sectors.Count == 1)
+			else if (sectors.Count == 1)
 			{
 				sector = sectors[0];
 			}