diff --git a/rollout/experiment.go b/rollout/experiment.go
index 807d44ddb7..a000fe014e 100644
--- a/rollout/experiment.go
+++ b/rollout/experiment.go
@@ -230,7 +230,7 @@ func (c *rolloutContext) createExperimentWithCollisionHandling(newEx *v1alpha1.E
 			// we likely reconciled the rollout with a stale cache (quite common).
 			return existingEx, nil
 		}
-		newEx.Name = fmt.Sprintf("%s.%d", baseName, collisionCount)
+		newEx.Name = fmt.Sprintf("%s-%d", baseName, collisionCount)
 		collisionCount++
 	}
 }
diff --git a/rollout/experiment_test.go b/rollout/experiment_test.go
index 48c05e4233..6ba0ca43b0 100644
--- a/rollout/experiment_test.go
+++ b/rollout/experiment_test.go
@@ -165,7 +165,7 @@ func TestCreateExperimentWithCollision(t *testing.T) {
 
 	f.run(getKey(r2, t))
 	createdEx := f.getCreatedExperiment(createExIndex)
-	assert.Equal(t, ex.Name+".1", createdEx.Name)
+	assert.Equal(t, ex.Name+"-1", createdEx.Name)
 	patch := f.getPatchedRollout(patchIndex)
 	expectedPatch := `{
 		"status": {