diff --git a/internal/telemetry/metrics/providers.go b/internal/telemetry/metrics/providers.go
index 5c1baf315..8319a4545 100644
--- a/internal/telemetry/metrics/providers.go
+++ b/internal/telemetry/metrics/providers.go
@@ -196,6 +196,8 @@ func ocExport(name string, exporter *ocprom.Exporter, r *http.Request, labels []
 	return func(context.Context) promProducerResult {
 		// Ensure we don't get entangled with compression from ocprom
 		r.Header.Del("Accept-Encoding")
+		// Request metrics in text format.
+		r.Header.Set("Accept", "text/plain")
 
 		rec := httptest.NewRecorder()
 		exporter.ServeHTTP(rec, r)
diff --git a/internal/telemetry/metrics/providers_test.go b/internal/telemetry/metrics/providers_test.go
index aa795401c..9cc2e8afc 100644
--- a/internal/telemetry/metrics/providers_test.go
+++ b/internal/telemetry/metrics/providers_test.go
@@ -28,12 +28,15 @@ envoy_server_initialization_time_ms_bucket{le="1000"} 1
 	}
 }
 
-func getMetrics(t *testing.T, envoyURL *url.URL) []byte {
+func getMetrics(t *testing.T, envoyURL *url.URL, header http.Header) []byte {
 	h, err := PrometheusHandler([]ScrapeEndpoint{{Name: "envoy", URL: *envoyURL}}, "test_installation_id", time.Second*20)
 	if err != nil {
 		t.Fatal(err)
 	}
 	req := httptest.NewRequest(http.MethodGet, "http://test.local/metrics", nil)
+	if header != nil {
+		req.Header = header
+	}
 	rec := httptest.NewRecorder()
 	h.ServeHTTP(rec, req)
 
@@ -48,7 +51,7 @@ func getMetrics(t *testing.T, envoyURL *url.URL) []byte {
 
 func Test_PrometheusHandler(t *testing.T) {
 	t.Run("no envoy", func(t *testing.T) {
-		b := getMetrics(t, &url.URL{})
+		b := getMetrics(t, &url.URL{}, nil)
 
 		if m, _ := regexp.Match(`(?m)^# HELP .*`, b); !m {
 			t.Errorf("Metrics endpoint did not contain any help messages: %s", b)
@@ -58,7 +61,22 @@ func Test_PrometheusHandler(t *testing.T) {
 	t.Run("with envoy", func(t *testing.T) {
 		fakeEnvoyMetricsServer := httptest.NewServer(newEnvoyMetricsHandler())
 		envoyURL, _ := url.Parse(fakeEnvoyMetricsServer.URL)
-		b := getMetrics(t, envoyURL)
+		b := getMetrics(t, envoyURL, nil)
+
+		if m, _ := regexp.Match(`(?m)^go_.*`, b); !m {
+			t.Errorf("Metrics endpoint did not contain internal metrics: %s", b)
+		}
+		if m, _ := regexp.Match(`(?m)^# TYPE envoy_.*`, b); !m {
+			t.Errorf("Metrics endpoint did not contain envoy metrics: %s", b)
+		}
+	})
+
+	t.Run("with envoy, request protobuf format", func(t *testing.T) {
+		fakeEnvoyMetricsServer := httptest.NewServer(newEnvoyMetricsHandler())
+		envoyURL, _ := url.Parse(fakeEnvoyMetricsServer.URL)
+		header := http.Header{}
+		header.Set("Accept", "application/vnd.google.protobuf;proto=io.prometheus.client.MetricFamily;encoding=delimited")
+		b := getMetrics(t, envoyURL, header)
 
 		if m, _ := regexp.Match(`(?m)^go_.*`, b); !m {
 			t.Errorf("Metrics endpoint did not contain internal metrics: %s", b)