diff --git a/glean_parser/schemas/metrics.1-0-0.schema.yaml b/glean_parser/schemas/metrics.1-0-0.schema.yaml
index b03134b3d..650e466a1 100644
--- a/glean_parser/schemas/metrics.1-0-0.schema.yaml
+++ b/glean_parser/schemas/metrics.1-0-0.schema.yaml
@@ -48,7 +48,7 @@ definitions:
 
   labeled_metric_id:
     type: string
-    pattern: "^[a-z_][a-z0-9_-]{0,29}(\\.[a-z0-9_-]{0,29})*$"
+    pattern: "^[a-z_][a-z0-9_-]{0,29}(\\.[a-z_][a-z0-9_-]{0,29})*$"
     maxLength: 71  # Note: this should be category + metric + 1
 
   metric:
diff --git a/tests/data/core.yaml b/tests/data/core.yaml
index c600c19ef..101886f29 100644
--- a/tests/data/core.yaml
+++ b/tests/data/core.yaml
@@ -95,7 +95,6 @@ core_ping:
       - this_is_fine_too
       - this.is_still_fine
       - thisisfine
-      - this.is_fine.2
       - _.is_fine
       - this.is-fine
       - this-is-fine