diff --git a/flatmap/expand.go b/flatmap/expand.go
index 2c0a9266b7..87bc9b5dab 100644
--- a/flatmap/expand.go
+++ b/flatmap/expand.go
@@ -61,12 +61,15 @@ func expandMap(m map[string]string, prefix string) map[string]interface{} {
 
 		key := k[len(prefix):]
 		idx := strings.Index(key, ".")
-		if idx == -1 {
-			idx = len(k)
+		if idx != -1 {
+			key = key[:idx]
+		}
+		if _, ok := result[key]; ok {
+			continue
 		}
 
 		// It contains a period, so it is a more complex structure
-		result[key] = Expand(m, k[:idx])
+		result[key] = Expand(m, k[:len(prefix)+len(key)])
 	}
 
 	return result
diff --git a/flatmap/expand_test.go b/flatmap/expand_test.go
index 6ad54945e3..baf68e6a97 100644
--- a/flatmap/expand_test.go
+++ b/flatmap/expand_test.go
@@ -49,12 +49,32 @@ func TestExpand(t *testing.T) {
 				},
 			},
 		},
+
+		{
+			Map: map[string]string{
+				"foo.#":         "1",
+				"foo.0.name":    "bar",
+				"foo.0.ports.#": "2",
+				"foo.0.ports.0": "1",
+				"foo.0.ports.1": "2",
+			},
+			Key: "foo",
+			Output: []interface{}{
+				map[string]interface{}{
+					"name": "bar",
+					"ports": []interface{}{
+						1,
+						2,
+					},
+				},
+			},
+		},
 	}
 
 	for _, tc := range cases {
 		actual := Expand(tc.Map, tc.Key)
 		if !reflect.DeepEqual(actual, tc.Output) {
-			t.Fatalf(
+			t.Errorf(
 				"Key: %v\nMap:\n\n%#v\n\nOutput:\n\n%#v\n\nExpected:\n\n%#v\n",
 				tc.Key,
 				tc.Map,
diff --git a/flatmap/flatten_test.go b/flatmap/flatten_test.go
index 0bd15e8821..9f21d23643 100644
--- a/flatmap/flatten_test.go
+++ b/flatmap/flatten_test.go
@@ -52,6 +52,27 @@ func TestFlatten(t *testing.T) {
 				"foo.0.enabled": "true",
 			},
 		},
+
+		{
+			Input: map[string]interface{}{
+				"foo": []map[interface{}]interface{}{
+					map[interface{}]interface{}{
+						"name": "bar",
+						"ports": []string{
+							"1",
+							"2",
+						},
+					},
+				},
+			},
+			Output: map[string]string{
+				"foo.#":         "1",
+				"foo.0.name":    "bar",
+				"foo.0.ports.#": "2",
+				"foo.0.ports.0": "1",
+				"foo.0.ports.1": "2",
+			},
+		},
 	}
 
 	for _, tc := range cases {